Please help with math question!?!


Question: Please help with math question!?
x = 2y + 3
6y - 6x = -42

x=
y=

Answers:

Perform substitution. In this equation set, the variables x and y are the SAME so.... you can carry them between the two equations. In this case, it's easy because you already have one variable solved for you, x.

You know that x = 2y+3, so... plug it into the 2nd equation to eliminate one variable, and we have:
6y - 6(2y+3) = -42

Distribute the -6
6y - 12y -18 = -42

Move/Combine like terms
-6y = -24

Divide both sides by -6
y = 4

Now that you know what y is, plug that back into the first equation to find x

x = 2(4) +3
x = 8 + 3
x = 11

x= 11
y= 4

Double check by pluging in the numbers into one of the equations if you're not sure.



This is a system of equations

Substitute the first equation into the second
6y-6(2y+3)=-42
6y-12y-18=-42
-6y=-42+18
y=-24/-6
y=4

Substitute y is = 4 in the first equation
x=2(4)+3
x=8+3
x=11


x=11, y=4



x = 2y + 3---> -2y = -x + 3----> y = 1/2 x -3


6y - 6x = -42-----> y = x - 7


setting them equal

x - 7 = 1/2 x -3-----> 1/2 x = 4--------> x = 8



Im almost positive X is 6 but i cant figure out Y i will keep trying or its gonna irritate me that i cant figure it out. hope that helps :)

~Lacie Lou :)

My 8th grade math class :)



damn son




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