A - 3b = 4 . . . . (1)
a = b - 2 . . . . . (2)
Putting (2) into (1), we have
b - 2 - 3b = 4
-2b = 4 + 2 = 6
b = 6/-2 = -3
From (1), a = b - 2 = -3 - 2 = -5
Hence, solution = (-5, -3)
$10.18 Add all the numbers then divide by the amount in this case 5
He answered .85, 85% or 17/20 correct on the test.
