Step 1) Solve the first equation for #x#:
#x - 4y + color(red)(4y) = 2 + color(red)(4y)#
#x - 0 = 2 + 4y#
#x = 2 + 4y#
Step 2) Substitute #(2 + 4y)# for #x# in the second equation and solve for #y#:
#3x + 4y = -10# becomes:
#3(2 + 4y) + 4y = -10#
#(3 xx 2) + (3 xx 4y) + 4y = -10#
#6 + 12y + 4y = -10#
#6 + (12 + 4)y = -10#
#6 + 16y = -10#
#6 - color(red)(6) + 16y = -10 - color(red)(6)#
#0 + 16y = -16#
#16y = -16#
#(16y)/color(red)(16) = -16/color(red)(16)#
#(color(red)(cancel(color(black)(16)))y)/cancel(color(red)(16)) = -1#
#y = -1#
Step 3) Substitute #-1# for #y# in the solution to the first equation at the end of Step 1 and calculate #x#:
#x = 2 + 4y# becomes:
#x = 2 + (4 xx -1)#
#x = 2 + (-4)#
#x = 2 - 4#
#x = -2#
The Solution Is:
#x = -2# and #y = -1#
Or
#(-2, -1)#
