Someone pleaseee answer #2 #3 and #4 on lesson 7.9!

The equation 9 y minus 6 x = 36 is written in standard form. What is the first step when writing an equivalent equation which so

enot [183]

Answer:

D. Subtract 9y from both sides of the equation.

Step-by-step explanation:

A. Divide both sides of the equation by 36.

B. Multiply both sides of the equation by 6.

C. Add 9y to both sides of the equation.

D. Subtract 9y from both sides of the equation.

Given:

9y - 6x = 36

To solve for x

Step 1: subtract 9y from both sides

9y - 6x - 9y = 36 - 9y

- 6x = 36 - 9y

Step 2: Divide both sides by -6

- 6x / -6 = (36 - 9y) / - 6

x = (36 - 9y) / - 6

The answer is

x = (36 - 9y) / - 6

8 0

2 years ago

Find x (Will mark brainliest if you are right)

Marizza181 [45]

Answer:

Step-by-step explanation:

(-3x + 2)(45x + 21) + (-4x + 25) = 50

-135x^2 - 63x + 90x + 42 - 4x + 25 = 50

-135x^2 + 23x + 67 = 50

-135x^2 + 23x + 67 - 50 = 0

-135x^2 + 23x + 17 = 0

quadratic formula : x = (-b ± √b^2 - 4ac)/2a

a = -135, b = 23, c = 17

x = -23 ± √23^2 - 4(-135)(17) / (2(-135)

x = (-23 ±√9709 )/ -270

x = 23/270 ± 1 / 270√9709/270

x = 0.4501 or x = - 0.2798 <=== these answers are rounded

4 0

2 years ago

There are 18 oranges in box A and 36 in box B, what is the ratio of box A to box B

Nana76 [90]

Answer:

1 : 2

Step-by-step explanation:

Express the ratio as the number of oranges in each box, that is

box A : box B

= 18 : 36

Simplify the ratio by dividing both parts by 18, thus

ratio = 1 : 2 ← in simplest form

7 0

2 years ago

Solve. 4x−y−2z=−8 −2x+4z=−4 x+2y=6 Enter your answer, in the form (x,y,z), in the boxes in simplest terms. x= y= z=

ladessa [460]

Answer:

(-2, 4, -2)

x=-2, y=4, z=-2.

Step-by-step explanation:

So we have the three equations:

$4x-y-2z=-8\\-2x+4z=-4\\x+2y=6$

And we want to find the value of each variable.

To solve this system, first look at it and consider what you should try to do.

So we can see that the second and third equations both have an x.

Therefore, we can isolate the variables for the second and third equation and then substitute them into the first equation to make the first equation all xs.

Therefore, let's first isolate the variable in the second and third equation.

Second Equation:

$-2x+4z=-4$

First, divide everything by -2 to simplify things:

$x-2z=2$

Subtract x from both sides. The xs on the left cancel:

$(x-2z)-x=2-x\\-2z=2-x$

Now, divide everything by -2 to isolate the z:

$z=-\frac{2-x}{2}$

So we've isolated the z variable. Now, do the same to the y variable in the third equation:

$x+2y=6$

Subtract x from both sides:

$2y=6-x$

Divide both sides by 2:

$y=\frac{6-x}{2}$

Now that we've isolated the y and z variables, plug them back into the first equation. Therefore:

$4x-y-2z=-8\\4x-(\frac{6-x}{2})-2(-\frac{2-x}{2})=-8$

Distribute the third term. The -2s cancel out:

$4x-(\frac{6-x}{2})+(2-x)=-8$

Since there is still a fraction, multiply everything by 2 to remove it:

$2(4x-(\frac{6-x}{2})+(2-x))=2(-8)$

Distribute:

$8x-(6-x)+2(2-x)=-16\\8x-6+x+4-2x=-16$

Combine like terms:

$8x+x-2x-6+4=-16\\7x-2=-16$

Add 2 to both sides:

$7x=-14$

Divide both sides by 7:

$(7x)/7=(-14)/7\\x=-2$

Therefore, x is -2.

Now, plug this back into the second and third simplified equations to get the other values.

Second equation:

$z=-\frac{2-x}{2}\\ z=-\frac{2-(-2)}{2}\\z=-\frac{4}{2}\\z=-2$

Third equation:

$y=\frac{6-x}{2}\\y=\frac{6-(-2)}{2}\\y=\frac{8}{2}\\y=4$

Therefore, the solution is (-2, 4, -2)

3 0

2 years ago

Read 2 more answers

There are 49 floors. There are 26 offices on each of the bottom31 floors. The top of 18 floors have 38 offices. About how many o

zysi [14]

31 × 26 = 806

18 × 38 = 684

806 + 684 = 1490

7 0

2 years ago