Help please !!!!!!!!!!!!!!!!!!
Answer:
n = 59
Step-by-step explanation:
There's definitely a better way, i just did math randomly but here goes:
First i squared both sides. which gets you:
[tex](\sqrt{n+5}-\sqrt{n-10} )(\sqrt{n+5}-\sqrt{n-10} )=1^2\\\\n+5 -2\sqrt{(n+5)(n-10)} +n-10=1[/tex]
Cleaning this up gives you:
[tex]2n-5 -2\sqrt{(n+5)(n-10)}=1[/tex]
Now move everything to the other side so we can square this equation again
[tex]-2\sqrt{(n+5)(n-10)}=-2n+6[/tex]
Divide both sides by -2
[tex]\sqrt{(n+5)(n-10)}=n-3[/tex]
square again
[tex](n+5)(n-10)=(n-3)^2\\n^2-5n-50=n^2-6n+9[/tex]
subtract n^2 from both sides, add 6n, and add 50
[tex]-5n-50=-6n+9\\n-50 = 9\\n=59[/tex]
Put this back into the equation and you get a correct answer!
sqrt(59 + 5) = sqrt(64) = 8
sqrt(59-10) = sqrt(49) = 7
8 - 7 = 1
A parabola y=x^2 is what type of function?
an even function
an odd function
an asymmetric function
a one to one function
Step-by-step explanation:
The parabola has a line of symmetry at x=0 so that means we can reflect the function across the y axis and it will remain unchanged so the answer is even function.
Which expression is equivalent to 6 (3x + 4)?
18.1 + 24
183 +4
92 +10
91 +4
Pls hurry
it took 5 hours to mow 6 yards. at the rate, how many yards can be mowed in 20 hours
Answer:
24 yards
Step-by-step explanation:
Given: 5 hours to mow 6 yards.
To find: At the same rate, how many yards can be mowed in 20 hours?
Solution: There are lots of different ways of solving this but I will show you setting up fractions to know how much 5 hours are for 6 yards let "x" be the variable
Step 1: Multiply all terms by the same value to eliminate fraction denominators
[tex]\frac{6}{5} = \frac{x}{20} \\\\20*\frac{6}{5} = 20 * \frac{x}{20}[/tex]
Step 2: Cancel multiplied terms that are in the denominator
[tex]20*\frac{6}{5} = 20 * \frac{x}{20}\\\\20 * \frac{6}{5} = x[/tex]
Step 3: Multiply the numbers
[tex]20 * \frac{6}{5} = x\\\\24 = x[/tex]
Step 4: Move the variable to the left
[tex]24 = x\\\\x = 24[/tex]
Therefore, 24 yards can be mowed in 20 hours.
vTo estimate the parameter stated in question 2, the following was done. A simple random sample of 22 students who attended a review session was selected, and the mean grade on test 7 for this sample of 22 students was 85 with a standard deviation of 9.8. An independent simple random sample of 47 students who did not attend a review session was selected, and the mean grade on test 7 was 77 with a standard deviation of 10.6. If appropriate, use this information to calculate and interpret a 90% confidence interval for the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session.
Answer:
The 90% confidence interval for the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session is (3.7, 12.3).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction between normal variables.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
A simple random sample of 22 students who attended a review session was selected, and the mean grade on test 7 for this sample of 22 students was 85 with a standard deviation of 9.8.
This means that:
[tex]\mu_A = 85, s_A = \frac{9.8}{\sqrt{22}} = 2.09[/tex]
An independent simple random sample of 47 students who did not attend a review session was selected, and the mean grade on test 7 was 77 with a standard deviation of 10.6.
This means that:
[tex]\mu_N = 77, s_N = \frac{10.6}{\sqrt{47}} = 1.55[/tex]
Distribution of the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session.
Mean:
[tex]\mu = \mu_A - \mu_N = 85 - 77 = 8[/tex]
Standard deviation:
[tex]s = \sqrt{s_A^2 + s_B^2} = \sqrt{2.09^2 + 1.55^2} = 2.6[/tex]
Confidence interval:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.9}{2} = 0.05[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.05 = 0.95[/tex], so Z = 1.645.
Now, find the margin of error M as such
[tex]M = zs[/tex]
So
[tex]M = 1.645*2.6 = 4.3[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 8 - 4.3 = 3.7
The upper end of the interval is the sample mean added to M. So it is 8 + 4.3 = 12.3
The 90% confidence interval for the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session is (3.7, 12.3).
Explain how to graph the following including asymptotes and key features. f(x)=3^x+2
Answer:
y=2
Step-by-step explanation:
Ms. Silvia earns $3 every time she sells a cupcake. If she earns $15, how many cupcakes did she sell?
Answer:
Okay very easy, The answer is: She sold 5 cupcakes.
Step-by-step explanation:
She sold 5 cupcakes
Because if you add 3 till you get to 15 you get 5
Which best describes the numbers satisfying the inequality x less-than 7?
A all numbers greater than 7
B all numbers less than 7
C all numbers greater than and including 7
D all numbers less than and including 7
Answer:
B all numbers less than 7
Step-by-step explanation:
x < 7
B all numbers less than 7
----------------------
< is less than
≤ is less than or equal
> is greater than
≥ is greater than or equal
Answer:
b XD
Step-by-step explanation:
ON A RECENT MATH TEST MARY SCORED 14 OF 16 CORRECT. JOHN SCORED 23 OF 26AND JOE SCORED 9 OF 11 CORRECT. WHO ACHIEVED THE HIGHER SCORE?
Answer:
I think the answer is mary
Answer:
John
Step-by-step explanation:
Mary: 87%-88% (0.875)
John: 88% (0.884)
Joe: 81% (0.818)
Is either x = 8 or x = 10 a solution to 5x < 52?
A. x = 8 is a solution, but x = 10 is not.
B. Neither is a solution.
O C. x = 10 is a solution, but x = 8 is not.
D. They are both solutions.
Answer:
B. neither of them are solutions
PLS HELP ME ASAP! FOR 15 POINTS AND DONT GIVE ME A LINK
Select the correct answer.
What is the solution to this system of equations?
x − 2y = 15
2x + 4y = -18
A. x = 1, y = -6
B. x = 1, y = -7
C. x = 3, y = -6
D. x = 3, y = -7
Answer:
C. x = 3, y = -6 is the answer.
Step-by-step explanation:
1. Isolate x for x = 2y = 15 -> x = 15 + 2y
2. Substitute x = 15 + 2y -> [2 (15 + 2y) + 4y = -18]
3. Simplify -> [30 + 8y = -18)
4. Isolate y for 30 + 8y = -18 -> y = -6
5. For x = 15 + 2y, substitute y = -6 -> x = 15 + 2(-6)
So, x = 3 and y = -6 are the solutions to this system of equations.
Hope this helps! :)
And also you should use Symbolab, it gives all the answers and steps
which measurement is closest to the area of the shaded region in square inches
If you invest $2500 at a rate of 3.5%, how much money will be in the
account after 10 years if it is compounded yearly?
Answer:
A = $3,526.50
Step-by-step explanation:
First, convert R as a percent to r as a decimal
r = [tex]\frac{R}{100}[/tex]
r = [tex]\frac{3.5}{100}[/tex]
r = 0.035 rate per year,
Then solve the equation for A
A = P(1 + [tex]\frac{r}{n}[/tex])nt
A = 2,500.00(1 + [tex]\frac{0.035}{1}[/tex])(1)(10)
A = 2,500.00(1 + 0.035)(10)
A = $3,526.50
Hence:
The total amount of over 10 years is $3,526.50.
What is the volume, in cubic meters, of a cylinder with a height of 3 meters and a base
radius of 4 meters, to the nearest tenths place?
Answer:
answer is 150
Step-by-step explanation:
hope it helps
Lauren went to a store to buy some clothes. The shirts were selling at a 20% discount. A pair of pants cost $5 less than 3 times the original cost of a shirt.
If she spent $36 in all, what was the original cost of a shirt?
Answer:
OMG
Step-by-step explanation:
I had the same question
Answer:
$10.79
Step-by-step explanation:
x = original cost of one t shirt
We can build this equation
x - (20/100) x + 3x- 5 = 36
-1/5x + 4x = 41
-x + 20x = 205
19x = 205
x = $10.79
2
Find the lateral area and the surface area of the cone. Keep answer in exact form.
12 ft
16 ft
lateral area
surface area -
Answer:
I think:
192 lateral area
56 surface area
If Im wroung Im very sorry
2. A serving of soup is 275 milliliters.
Will 6 servings of soup fit into a jar that holds up to 1.5 liters of liquid? Explain.
Answer:
No, the 6 servings of soup is 1675 milliliters, which is greater than 1.5 liters.
Step-by-step explanation:
So we already know that 1 surving of soup is 275 milliliters.
We have 6 survings of this soup.
We need to see if these 6 servings will fit in a 1.5 liter jar.
To find the total amount of mililers, we must multipy this by 6:
275*6
=
1650
Remember that 1 liter is equal to 1000 mililiters. To find the 1650 mililliters in liters, we must divide by 1000:
1650/1000
=
1.65
This number is greater than 1.5 liters, which is how much soup the jar can store.
So the answer is no, the 6 servings of soup cannot fit in the jar.
A child pool is 3.8 feet wide 5.5 feet long and 1.2 fee deep, what is the volume of the pool?
Answer:
25.08
Step-by-step explanation:
Answer:
25.08 cubic feet
Step-by-step explanation:
v = l * w * h
v = 5.5 * 3.8 * 1.2
v = 25.08 cubic feet
Given: Triangle ABC with AB = 42 and BC = 20. Which of the following are possible lengths for AC?
Answer:
46.5
Step-by-step explanation:
Using the Pythagoras' Theorem, this is the answer you would get.
I hope this helped☺
PLEASE HELP ME!!!! I WILL MARK BRAINLIEST
find the length of the third side!
THANK YOU!
Answer:
The answer is 7
Step-by-step explanation:
[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]
for our purposes we must rearrange this problem to find one of the sides, not the hypotenuse
[tex] {a}^{2} = {c}^{2} - {b}^{2} [/tex]
plugging in our numbers we get
[tex] {25}^{2} - {24}^{2} = 49[/tex]
[tex] \sqrt{49} = 7[/tex]
a(-6) = -42 what is a?
Answer:
it is 7
Step-by-step explanation:
Ten years ago, Scott bought a board game for $30. That board game has now increased it's value by 83%.
100
What would be the price of that game now?
Answer:54.9
Step-by-step explanation:
How long would it take a cruise ship to travel 156 miles at an average speed of 26 mph
Answer:
The answer is 6 hours
Step-by-step explanation:
26x6=156
What is the length of the diagonal of a non -regulation tennis court with length 20 feet and width 15 feet
Answer:
25 feet
Step-by-step explanation:
using the sides 20 and 15, use the Pythagorean theorem to find the hypotenuse of the right triangle formed by the 2 side lengths and the diagonal.
[tex]a^{2} +b^{2} =c^{2} \\20^{2} +15^{2} =c^{2} \\400+225=c^{2} \\625=c^{2} \\25=c[/tex]
Write an algebraic expression for each word expression.
A number, n, divided by 9
Answer:
n/9
Step-by-step explanation:
Answer:
n/9
Step-by-step explanation:
Jason baked 7 pans of brownies. He gave ¼ of the brownies to his two sisters. How many pans of brownies did he give to his sisters? *
Step-by-step explanation:
7×1/4 = 1.75
1.75 ÷ 2 = 0.875 pans each
Consider the salt shaker shown.
5 cm
cm
What is the volume of the salt shaker, including the top? Round your answer to the nearest hundredth.
Volume of Salt Shaker =
Answer:
Volume of salt shaker = 42.4 cm³ (Approx.)
Step-by-step explanation:
Given:
Height of salt shaker = 5 cm
Diameter of salt shaker = 3 cm
Find:
Volume of salt shaker
Computation:
Radius of salt shaker = Diameter of salt shaker / 2
Radius of salt shaker = 3 / 2
Radius of salt shaker = 1.5 cm
Volume of salt shaker = Volume of cylinder + Volume of Hemisphere
Volume of salt shaker = πr²h + (2/3)πr³
Volume of salt shaker = (3.14)(1.5)²(5) + (2/3)(3.14)(1.5)³
Volume of salt shaker = (3.14)(2.25)(5) + (0.667)(3.14)(3.375)
Volume of salt shaker = 35.325 + 7.068
Volume of salt shaker = 42.4 cm³ (Approx.)
Can someone help me with number 7 and 13 ? I graduate in a week an have to have this work done or I will not be graduating
18. A square board has an area of 95.63 square inches. Which is
closest to the length of one side of the board?
F 10 in
G9 in
H 48 in
) 24 in
Answer:
10 in
Step-by-step explanation:
What is the greatest common factor (GCF) of 24 and 40?
Question:
What is the greatest common factor (GCF) of 24 and 40?
Answer:
8
Step-by-step explanation:
Answer:
8
Step-by-step explanation:
40=2×2×2×5
24=2×2×2×3 then we take the common 2×2×2=8