Question

1. find the value of the variable and state the postulate or theorem used to find the value of

Explanation:

Step1: Use the vertical angles theorem

Vertical angles are equal. So \(x + 15=90\)

Step2: Solve for \(x\)

Subtract 15 from both sides of the equation: \(x=90 - 15\)

Answer:

\(x = 75\)
The theorem used is the Vertical Angles Theorem.