Find the area of △ABC with side lengths b = 6 and c = 17, and included angle A = 135∘. Round your answer to the nearest tenth.

Step-by-step explanation:

we know that

The area of a triangle applying the law of sines is given by the formula

where

A is the included angle between the sides b and c

substitute the given values

the sum of all the angles in a triangle are equal to 180

so you can add   the 3 given angles together to equal 180:

5y + 2y + 2y = 180

or since all three angles have the same letter, combine the 3 angles to equal 180:

9y = 180