You can
put this solution on YOUR website!The substitution method always involves solving one of the equations for one of the variables in terms of the other one. It will help if you divide both sides of the first equation by 3:
9y = x+1
Next subtract 1 from each side in order to solve for x:
9y-1 = x
x= 9y-1
Substitute this into the second equation:
5y -4x = 8
5y - 4(_____) = 8
5y - 4(9y -1) = 8
5y -36 y + 4 = 8
-31y = 4
y = -4/31 (That's pretty ugly!)
x= 9y-1
x=9*(-4/31) -1
x= -36/31 - 31/31
x= -67/31 (That's ugly too!!)
Check in the second equation, especially since the answer is so ugly!
5y - 4x = 8
5(-4/31) -4(-67/31) = 8
-20/31 + 268/31=8
248/31 =8
8=8
It checks after all!!
R^2 at SCC
Substitute this value of y into the x= equation:
