1

Use the method of completing the square to transform the quadratic equation into the equation form (x – p)2 = q.

oee [108]

X^2-12x-9=0
Add 9 to both sides
x^2-12x=9
Add (b/2)^2 to both sides
x^2-12x+36=45
Factor
(x-6)^2=45
So C is the answer

8 0

4 years ago

Please help me in this question please

4vir4ik [10]

Answer:

The first one and the second one

Step-by-step explanation:

6 0

3 years ago

The elimination method is ideal for solving this system of equations. By which number must you multiply the second equation to e

shutvik [7]

Given:

The system of equations is

$x+3y=42$ ...(i)

$2x-y=14$ ...(ii)

To find:

The number that must be multiplied with the second equation to eliminate the y-variable.

Solution:

Coefficient of y variable in equation (i) is 3 and in equation (ii) is -1.

To eliminate y-variable the absolute value of coefficients of y-variables should be same.

So, we need to multiply the second equation by 3 to eliminate the y-variable

Multiplying equation (ii) by 3, we get

$6x-3y=42$ ...(iii)

Adding (i) and (iii), we get

$x+3y+6x-3y=42+42$

$7x=84$

Divide both sides by 7.

$x=12$

Put x=12 in (i).

$12+3y=42$

$3y=42-12$

$3y=30$

Divide both sides by 10.

$y=10$

Therefore, x=12 and y=10.

7 0

3 years ago

Read 2 more answers

The pipe fitting industry had 546.5 thousand jobs in 2015 and is expected to decline at an average rate of 3 thousand jobs per y

lesya692 [45]

Answer:

The amount of jobs from fitting industry shall decline in 5.5 percent from 2015 to 2025.

Step-by-step explanation:

Due to the assumption of a yearly average rate, a linear function model shall be used. The expected amount of jobs ( $n$ ) after a certain amount of years (t) is given by the following formula:

$n = n_{o} + \frac{\Delta n}{\Delta t}\cdot t$

Where:

$n_{o}$ - Initial amount of jobs in pipe fitting industry, measured in thousands.

$\frac{\Delta n}{\Delta t}$ - Average yearly rate, measured in thousands per year. (A decline is indicated by a negative sign)

If $n_{o} = 546.5$ , $t = 2025-2015 = 10\,years$ and $\frac{\Delta n}{\Delta t} = -3\,\frac{1}{years}$ , then:

$n = 546.5+\left(-3\,\frac{1}{year}\right)\cdot (10\,years)$

$n = 516.5$

The percent change in jobs from pipe fitting industry is calculated as follows:

$\%n = \left(1-\frac{n}{n_{o}}\right)\times 100\,\%$

$\% n = \left(1-\frac{516.5}{546.5}\right)\times 100\,\%$

$\%n = 5.5\,\%$

The amount of jobs from fitting industry shall decline in 5.5 percent from 2015 to 2025.

4 0

3 years ago

A manufacturer of banana chips would like to know whether its bag filling machine works correctly at the 402 gram setting. It is

lidiya [134]

Answer:

The value of t test statistics is -2.25.

Step-by-step explanation:

We are given that a manufacturer of banana chips would like to know whether its bag filling machine works correctly at the 402 gram setting. It is believed that the machine is under filling the bags.

A 25 bag sample had a mean of 393 grams with a standard deviation of 20.

Let $\mu$ = mean filling of bags by the machine.