The area of a triangle is 64 cm^2. Given AB=11 cm and BC=15 cm find angle ABC.
To determine the measure of the angle B, we'll have to use the following formula that gives the area of triangle:
A = leg1*leg2*sine of the angle included/2
Since the lengths of AB and BC and the value of the area of triangle are known, we'll replace them within the formula above:
64 = 11*15*sin B/2
We'll multiply both sides by 2:
128 = 165*sin B
sin B = 128/165
sin B = 0.775
B = 50.80 degrees
The included angle ABC measures 50.80 degrees.