Question

what is the value of x?

Explanation:

Step1: Use vertical angles property

Vertical angles are equal. So \(3x=x + 40\).

Step2: Solve the equation

Subtract \(x\) from both sides: \(3x-x=x + 40-x\), which gives \(2x=40\).
Divide both sides by 2: \(x=\frac{40}{2}\).

Answer:

\(20\)