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3 years ago

12

Joe is solving a quadratic function by graphing. He gets -1, -2, and 2 as the solutions to the quadratic. What error did Joe mak

e and what is the correct answer to the quadratic?

1 answer:

svetlana [45]3 years ago

3 0

Answer:

There are only two roots of a quadratic.

Step-by-step explanation:

Not sure how Joe got three, but he did something incorrectly.

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Solve for x<br> n= 2x+1 / 2<br><br> x=_____

Eduardwww [97]

Answer:

x = n/2 - 1/4

Step-by-step explanation:

isolate the variable by dividing each side by factors that don't contain the variable

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3 years ago

PLEASE ANSWER ILL GIVE YOU POINTS <3

Kitty [74]

Answer:

s stands for the weight of the cat

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2 years ago

wlad13 [49]

Pythagorean theorem(√82)^2 = 9^2 + x^2

x = 1 cm

15^2 = 9^2 + y^2

y = 12 cm.

12-1 = 11

Area = 9*11 = 99 cm^2

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3 years ago

An engineer travels daily from home tothelaboratory each morning with an average commutetime of 24.6 minutes with a standard dev

charle [14.2K]

Answer:

1.74% probability that the commute takes more than 32 minutes.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 24.6, \sigma = 3.5$

a.What is the probability that the commute takes more than 32 minutes?

This is 1 subtracted by the pvalue of Z when X = 32. So:

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{32 - 24.6}{3.5}$

$Z = 2.11$

$Z = 2.11$ has a pvalue of 0.9826.

So there is a 1-0.9826 = 0.0174 = 1.74% probability that the commute takes more than 32 minutes.

7 0

3 years ago

First make a substitution and then use integration by parts to evaluate the integral. (Use C for the constant of integration.) x

e-lub [12.9K]

Answer:

$(\frac{x^{2}-25}{2})ln(5+x)-\frac{x^{2}}{4}+\frac{5x}{2}+C$

Step-by-step explanation:

Ok, so we start by setting the integral up. The integral we need to solve is:

$\int x ln(5+x)dx$

so according to the instructions of the problem, we need to start by using some substitution. The substitution will be done as follows:

U=5+x

du=dx

x=U-5

so when substituting the integral will look like this:

$\int (U-5) ln(U)dU$

now we can go ahead and integrate by parts, remember the integration by parts formula looks like this:

$\int (pq')=pq-\int qp'$

so we must define p, q, p' and q':

p=ln U

$p'=\frac{1}{U}dU$

$q=\frac{U^{2}}{2}-5U$

q'=U-5

and now we plug these into the formula:

$\int (U-5)lnUdU=(\frac{U^{2}}{2}-5U)lnU-\int \frac{\frac{U^{2}}{2}-5U}{U}dU$

Which simplifies to:

$\int (U-5)lnUdU=(\frac{U^{2}}{2}-5U)lnU-\int (\frac{U}{2}-5)dU$

Which solves to:

$\int (U-5)lnUdU=(\frac{U^{2}}{2}-5U)lnU-\frac{U^{2}}{4}+5U+C$

so we can substitute U back, so we get:

$\int xln(x+5)dU=(\frac{(x+5)^{2}}{2}-5(x+5))ln(x+5)-\frac{(x+5)^{2}}{4}+5(x+5)+C$

and now we can simplify:

$\int xln(x+5)dU=(\frac{x^{2}}{2}+5x+\frac{25}{2}-25-5x)ln(5+x)-\frac{x^{2}+10x+25}{4}+25+5x+C$

$\int xln(x+5)dU=(\frac{x^{2}-25}{2})ln(5+x)-\frac{x^{2}}{4}-\frac{5x}{2}-\frac{25}{4}+25+5x+C$

$\int xln(x+5)dU=(\frac{x^{2}-25}{2})ln(5+x)-\frac{x^{2}}{4}+\frac{5x}{2}+C$

notice how all the constants were combined into one big constant C.

7 0

4 years ago