Question

Triangle ABC has angle measures as noted below. Please note this triangle is not drawn to scale, and the longest leg of the figure may not be the longest leg of the actual triangle.

You will need to use the expressions for the angles given below.
m∠A) 3(x + 5)
m∠B) 5x+15
m∠C) 7x

Identify the angle relationship and setup your equation with the given expressions.
What is the value of x? Show your work.
What is the measure of angle A, B, & C? Show your work and make sure to identify which is which.

Answer 1

<A=45°,<B=65°,<C=70°

Explanation:

<A=3(x+5)=3x+15

<B=5x+15

<C=7x

sum angles in a triangle is 180°

so,<A+<B+<C=180

(3x+15)+(5x+15)+(7x)=180

C.L.T

3x+5x+7x+15+15=180

15x+30=180

15x=180-30

15x=150

divide both sides by 15

x=10

<A=3(x+5)=3(10+5)=3(15)=45°

<B=5(10)+15=50+15=65°

<C=7(10)=70°