Question

so we have a small issue. I dont know how to figure this out and I dont know what equivalent means :/ so if you can help me that would be great. make sure you tell me how you got that answer. thank you guys!!!!​

Answer 1

Equivalent means "equal to"

Because we are looking for an equation that is not equivalent to 3y + x = 18, we need to find one that is not equal to 3y + x = 18.

First, lets try y = 6 - 1/3x

3y + x = 18

Divide the whole of both sides by 3

y + 1/3x = 6

Then, subtract 1/3x from each side

y = 6 - 1/3x

So, y = 6 - 1/3x IS equivalent to 3y + x = 18, so it is not the answer.

Next, lets try y - 5 = -1/3 (x - 3)

First, we need to distribute the -1/3 in the right side.

y - 5 = -1/3x + 1

Add 5 to each side

y = -1/3x + 6

Add 1/3x to each side

y + 1/3x = 6

So, y + 1/3x = 6 is NOT equivalent to 3y + x = 18, so it IS an answer.

Lets try the third one: y - 5 = 1/3(x + 3)

We need to use distributive property again on the right side

y - 5 = 1/3x + 1

Add 5 to each side

y = 1/3x + 6 is not equivalent to 3y + x = 18 so it IS and answer

Lets test the last one: 6y + 2x = 36

Divide the whole of each side by 2

3y + x = 18 IS equivalent to 3y + x = 18 so it is NOT an answer