x + 4 = 20
x = 16
-5x = 65
x = -13
4(y - 5) + y = 2y + 13
y = 11
x + 53 = 21
x = -32.
x/6 = 12
x = 72
7k - 8 + 2(k + 15) = 52 - k
k = 3
x - 7/8 = 3/4
x = 13/8
Press F11 Select menu option View > Enter Fullscreen for full-screen mode