A = (h * b) / 2
h = 2b + 2
A = 42
42 = (b(2b + 2)) / 2
42 = (2b^2 + 2b) / 2
42 = b^2 + b
b^2 + b - 42 = 0
(b + 7)(b - 6) = 0
b + 7 = 0
b = -7...nope..extraneous solution
b - 6 = 0
b = 6 <== base
h = 2b + 2
h = 2(6) + 2
h = 12 + 2
h = 14 <=== height (altitude)