Question

Last question hopefully.
This is elimination, explain to me how I can solve.
3x +3y=27
x+3y=-11

Answer 1

you are eliminating the variable. taking this word "eliminating" literally.

\(\normalsize\color{royalblue}{ \rm 3x+3y=27 }\)
\(\normalsize\color{royalblue}{ \rm x+3y=-11 }\)

I would multiply the second equation times -1, and add the equations together.

Answer 2

What am I multiplying by -1?

Answer 3

every term in the second equation.

Answer 4

what will your second equation look like?

Answer 5

-1x*3y=-11 .-.

Answer 6

\(\normalsize\color{blueviolet}{ x+3y=-11 }\)

\(\normalsize\color{blueviolet}{ (-1)x+(-1)3y=(-11)(-1) }\)

\(\normalsize\color{blueviolet}{ -x-3y=11 }\)

Answer 7

you will be getting;

\(\normalsize\color{teal}{ 3x +3y=27 }\)
\(\normalsize\color{teal}{ -x-3y=11 \large\color{white}{|}}\) makes sense?


then add the equations together

Answer 8

Yes.

Answer 9

when you add then, what do you get?

Answer 10

I got 8 and 4.5

Answer 11

for what?

Answer 12

Solving both equations. I think I ended up substituting.

Answer 13

you solved for x incorrectly whether 8 or 4.5 is for x.