Answer:
 x = 3 
Question: Find the value of x. 
Explanation:
Given:
- Triangle R T S is sitting on a horizontal line 
- Line S R extends through point Q to form exterior angle T R Q 
- m∠RTS is (25 x)°, m∠TSR is (57 + x)° , m∠TRQ is (45 x)° 
 
 Lets find the value of x 
 ∠TRQ is an exterior angle of Δ RTS at the vertex R 
 The opposite interior angles to vertex R are ∠RTS and ∠TSR 
∴ m∠TRQ = m∠RTS + m∠TSR 
m∠TRQ = (45 x)°
m∠RTS = (25 x)°
m∠TSR = (57 + x)°
Substitute these measures in the equation above
45 x = 25 x + 57 + x
45 x = 26 x + 57
19 x = 57
x = 3