X squared minus 3x minus 4 equals 0

PLEASE HELP ASAP WILL GIVE BRAINLIEST!!!

Tatiana [17]

Answer: 18 over x = -2x

Explanation:

Multiply all terms by the same value to eliminate fraction denominators,Cancel multiplied terms that are in the denominator and Re-order terms so constants are on the left,Combine exponents

Move terms to the left side

Rearrange terms

Common factor

Divide both sides of the equation by the same term

Use the quadratic formula

Simplify

Hope this helps (all the Steps to solve)

4 0

3 years ago

Which is the simplified form of (9c^-9)^-3 b 1/729 c^27

rosijanka [135]

ANSWER

$(9 {c}^{ - 9} )^{ - 3}=\frac{{c}^{ 27} }{729}$

EXPLANATION

The given expression is

$(9 {c}^{ - 9} )^{ - 3}$

Recall that:

$({a}^{m} )^{n} = {a}^{mn}$

We use the law of exponents to get

$(9 {c}^{ - 9} )^{ - 3} = 9^{ - 3} {c}^{ - 9 \times - 3}$

Let us multiply in the exponents to get:

$(9 {c}^{ - 9} )^{ - 3} = 9^{ - 3} {c}^{ 27}$

Recall again that:

${a}^{ - m} = \frac{1}{ {a}^{m} }$

This implies that:

$(9 {c}^{ - 9} )^{ - 3} = \frac{1}{ {9}^{ 3} } \times {c}^{ 27}$

We expand the power to get:

$(9 {c}^{ - 9} )^{ - 3} = \frac{1}{9 \times 9 \times 9} \times {c}^{ 27}$

$(9 {c}^{ - 9} )^{ - 3}=\frac{1}{729} \times {c}^{ 27}$

We multiply out to get:

$(9 {c}^{ - 9} )^{ - 3}=\frac{{c}^{ 27} }{729}$

7 0

3 years ago

The sum of the angle measures of a polygon with s sides is 2880. Find s. A. 20 B. 16 C. 17 D. 18

siniylev [52]

I think the answer is D. 18

8 0

3 years ago

Two different types of polishing solutions are being evaluated for possible use in a tumble-polish operation for manufacturing i

Nina [5.8K]

Answer:

$z=\frac{0.843-0.653}{\sqrt{0.748(1-0.748)(\frac{1}{300}+\frac{1}{300})}}=5.358$

$p_v =2*P(Z>5.358) = 4.2x10^{-8}$

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that we have singificantly differences between the two proportions.

Step-by-step explanation:

Data given and notation

$X_{1}=253$ represent the number with no defects in sample 1

$X_{2}=196$ represent the number with no defects in sample 1

$n_{1}=300$ sample 1

$n_{2}=300$ sample 2

$p_{1}=\frac{253}{300}=0.843$ represent the proportion of number with no defects in sample 1

$p_{2}=\frac{196}{300}=0.653$ represent the proportion of number with no defects in sample 2

z would represent the statistic (variable of interest)

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

$\alpha=0.05$ significance level given

Concepts and formulas to use

We need to conduct a hypothesis in order to check if is there is a difference in the the two proportions, the system of hypothesis would be:

Null hypothesis: $p_{1} - p_2}=0$

Alternative hypothesis: $p_{1} - p_{2} \neq 0$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{253+196}{300+300}=0.748$

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.843-0.653}{\sqrt{0.748(1-0.748)(\frac{1}{300}+\frac{1}{300})}}=5.358$

Statistical decision

Since is a two sided test the p value would be:

$p_v =2*P(Z>5.358) = 4.2x10^{-8}$

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that we have singificantly differences between the two proportions.

5 0

3 years ago

when each side of an inequality is multiplied or divided by a negative number the original inequality sign stays the same true o

Sophie [7]

Answer: FALSE

When you multiply an inequality by a negative number the inequality flips.

5 0

3 years ago