All categories

3 years ago

Y=x^2+3x-7 y-5x+8=0 how many solutions are there

1 answer:

7 0

X^2+3×-7=5x-8
X^2-2x+1=0
(X-1)(x-1)=0
X=1 x=1

Y=1^2+3*1-7
Y=1+3-7
Y=4-7
Y=-3

×=1 y=-3
Solution = (1,-3)
Answer= one solution

You might be interested in

Simplify the trigonometric expression.

Natasha_Volkova [10]

First we are going to find the common denominator of both fractions. To do that, we are going to multiply their denominators:
$(1+sin \alpha )(1-sin \alpha )=1-sin^2 \alpha$

Now we can rewrite our expression using the common denominator:
$\frac{1-sin \alpha }{1-sin^2 \alpha } + \frac{1+sin \alpha }{1-sin^2 \alpha} = \frac{2}{1-sin^2 \alpha}$

Finally, we can use the trig identities: $1-sin^2 \alpha =cos^2 \alpha$ and $sec \alpha = \frac{1}{cos \alpha }$ to simplify our trig expression:
$\frac{2}{cos^2\alpha}=2sec^2 \alpha$

We can conclude that the correct answer is the fourth one.

5 0

3 years ago

Read 2 more answers

A theory predicts that the mean age of stars within a particular type of star cluster is 3.3 billion years, with a standard devi

Luden [163]

Answer:

Null hypothesis: $\mu \leq 3.3$

Alternative hypothesis: $\mu > 3.3$

$z=\frac{3.4-3.3}{\frac{0.4}{\sqrt{50}}}=1.768$

Since is a one right tailed test the p value would be:

$p_v =P(z>1.768)=0.039$

Step-by-step explanation:

Data given and notation

$\bar X=3.4$ represent the sample mean

$\sigma=0.4$ represent the population deviation for the sample

$n=50$ sample size

$\mu_o =3.3$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses to be tested

We need to conduct a hypothesis in order to determine if the mean is higher than 3.3, the system of hypothesis would be:

Null hypothesis: $\mu \leq 3.3$

Alternative hypothesis: $\mu > 3.3$

Compute the test statistic

We know the population deviation, so for this case is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

We can replace in formula (1) the info given like this:

$z=\frac{3.4-3.3}{\frac{0.4}{\sqrt{50}}}=1.768$

P value

Since is a one right tailed test the p value would be:

$p_v =P(z>1.768)=0.039$

6 0

2 years ago

What is the simplified value of the expression below?-8 *(-3)

Readme [11.4K]

Answer: +24

Step-by-step explanation: To multiply (-8)(-3), remember that a negative times a negative is always a positive. So (-8)(-3) is +24.

7 0

2 years ago

Read 2 more answers

A train traveled 217 miles at an average speed of 62mph. for how many hours did the train travel

Natasha2012 [34]

Well, 217 miles ÷ 62 MPH is 3.5.
so it took the train 3.5 hours.

check it: 62 MPH x 3.5 hours, it went 217 miles

8 0

3 years ago

Add and Subtract Decimals to

Bogdan [553]

It should be 0.4 cause 0.4 is the same as 0.40

4 0

2 years ago