Question

Solving Systems by Substitution????

Answer 1

How do I solve problems like this: 2x+2y=38 and y=x+3

Answer 2

You know from the second equation that y = x+3. So, in the first equation, replace y with x + 3 and then solve that equation.

Answer 3

So then the first equation would be 2x+2x+3=38??

Answer 4

No. It would be
2x+2(x+3)=38 or
2x+2x+6=38

Answer 5

So then it would be 4x+6=38?simplified.

Answer 6

Yes. Now subtract 6 from both sides.

Answer 7

Ok so then it would be 4x=32.Next i need to divide each side by 4,right?

Answer 8

yes.

Answer 9

Ok so then x=8...How do I find y?

Answer 10

What does the second equation say?

Answer 11

y=x+3...so y=5?

Answer 12

The second equation says that if you want to find y you should take x and add 3.

Answer 13

Opps I was lookign at the x.y=11?

Answer 14

Yes. y = 11 and the solution to the system is the ordered pair (8,11)

Answer 15

Awesome thanks!!!

Answer 16

yw