Question

Y=3x+2
Y=x+12

Using the substitution method can someone help me?

Answer 1

you know that y = 3x + 2.....so just sub 3x + 2 in for y in the other equation..
y = x + 12
3x + 2 = x + 12 (subtract x from both sides)
3x - x + 2 = x - x + 12 (combine like terms)
2x + 2 = 12 (now subtract 2 from each side)
2x + 2 - 2 = 12 - 2 (combine like terms)
2x = 10 (now divide by 2 to get x by itself)
2x/2 = 10/2
x = 5
now sub 5 in for x in either of the original equations
y = x + 12
y = 5 + 12
y = 17
check...
y = 3x + 2
17 = 3(5) + 2
17 = 15 + 2
17 = 17 (correct)
ANSWER : x = 5 and y = 17 or (5,17)
Do you have any questions ? If so, please ask.

Answer 2

First solve the top equation for x, and put the result in the x of the 2nd equation. Looks like texa's gotcha covered!

Answer 3

Thanks for helping. I'll have another question up in a little bit. @texaschic101

Answer 4

I probably shouldn't have given the answer...but everyone needs a break sometimes :)

Answer 5

it really helped though i understand the steps and what to do. @texaschic101

Answer 6

thats good....but remember, if you have any question or concerns, please ask.

Answer 7

3x+y=10
y=x-2 you think you could help me out @texaschic101

Answer 8

you know that y = x - 2. So sub x - 2 in for y in the first equation.
Can you do that ?

Answer 9

I will walk you through this one.....I will not give the answer....you will find the answer.
Let me start you off...
3x + y = 10
3x + x - 2 = 10
now get the x's on one side and everything else on the other side.
Now it is your turn.

Answer 10

are you having trouble ?

Answer 11

3x + x - 2 = 10 (combine like terms then solve for x)
let me know if you need help.....