Drag an answer to each box to complete this paragraph proof.
Given: Triangle PQR with m∠P=(x)° , m∠Q=(3x)° , and m∠R=(5x)° .
Prove: x = 20
By the triangle sum theorem, the sum of the angles in a triangle is equal to 180°. Therefore using the given and triangle sum theorem, m∠P+m∠Q+m∠R=180° . Using the substitution property,