Question

If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to y from the second equation is substituted into the first equation.

2x – 5y = –3
6x – 3y = –3
Answer
2(2x + 1) – 5y = –3
2x – 5(2x + 1) = –3
2(–2x – 1) – 5y = –3
2x – 5(–2x – 1) = –3

Answer 1

Keke, do you have any thoughts on which one it could be?

Answer 2

I DONT KNOW I TRYED BREAKING IT DOWN BUT IT DIDNT WRK

Answer 3

B.!

Answer 4

Yep, Miss T has it, but she forgot to explain her steps so that Keke gets it too

Answer 5

2x - y = -4
2x = y - 4
2x + 4 = y

Answer 6

*5

Answer 7

Miss T, those are your steps? I thought you would have shown it this way:

In general when using substitution for systems of equations, you solve for x or y in one equation, then substitute the expression for the appropriate variable into the other equation.

In this particular situation, they want you to solve for y in the second equation, and replace its equivalent expression with y in the first equation.

In the second equation, solving for y yields the following:

6x – 3y = –3

3(2x-y) = -3

2x - y = -1
2x + 1= y

Therefore, y equals 2x + 1

In the first equation, we replace y with 2x+1 as follows:
2x – 5y = –3
2x-5(2x+1) = -3

And that is how we arrive at the correct solution, B

Answer 8

Sorry man I'm way to lazy for all that aha.

Answer 9

You didn't really have to do all of that. You could have just posted the correct solution steps.

Answer 10

But don't worry, I covered for you :D

Answer 11

No I expected the hero to swoop in and resolve it.!

Answer 12

Corney much.? Yeah I know again to lazy to come up with a decent joke.. Tisk Tisk Shake My Head.! -_-