Area of a triangle:
A = b * h / 2
A triangle base is 3 inches more than it's height.
This mean : b = h + 3
A = b * h / 2 = ( h + 3 ) * h / 2 = 35 in ^ 2
( h * h + 3 * h ) / 2 = 35
( h ^ 2 + 3 h ) / 2 = 35 Multiply both sides by 2
h ^ 2 + 3 h = 70 Subtract 70 to both sides
h ^ 2 + 3 h - 70 = 70 - 70
h ^ 2 + 3 h - 70 = 0
The solutions are :
h = - 10
and
h = 7
Height can't be negative so :
h = 7 in
b = h + 3 = 7 + 3 = 10 in
A = 10 * 7 / 2 = 70 / 2 = 35 in ^ 2
