Why are you taking a map test in january
3x + 4y = 31
2x - 4y = -6
*The +4 and -4 in the center of the equation cancel out because 4-4 = 0*
3x = 31
2x = -6
------------
*add like terms*
3x + 2x = 5x
31 - 6 = 25
So now you should have this written on your paper ... > 5x = 25
*Divide by 5 on each side*
5x = 25
_ _
5 5
x = 5
Subsitution
solve for y in first equation
add 2x to both sides
y=2x+8
sub 2x+8 for y in second equation
16+4x=2(2x+8)
divide both sides by 2
8+2x=2x+8
true
there are infinite solutions for x
therefor infinite soltions for y
there are an infinite number of solutions
It is y=x-150 because x−150+150=y+150