Find the area of the triangle. Round your answer to one decimal place. C = 150°, a = 15, b = 12

Answer 1

Hello Titus,

You have to know the area of triangle with 2 sides and one angle ,

the formula is if Area A = ab(sin C ) / 2

plugging the values from above problem ,

A = 15 * 12 ( sin 150°) / 2

value of sin 150° same as Sin 30° , that is equal to positive 1/2

So, A = 15 * 12 * ( 1/2 ) /2

A = 15* 12* 1/4 ( you can calculate your own way )

A = 45 sq. units this is Area of the Triangle

Answer 2

Law of Cosines:

c² = 12² + 15² - 2(12)(15) cos 150°

Law of Sines

sin 150° / c = sin B / 12

m∠A = 180° - 150º - m∠B