Question

lines m and n are parallel. find the measure of ∠a. m∠a = ?°

Explanation:

Step1: Use the property of parallel lines and transversal

When two parallel lines \(M\) and \(N\) are cut by a transversal, consecutive interior angles are supplementary. That is, \(\angle a+99^{\circ}=180^{\circ}\)

Step2: Solve for \(\angle a\)

Subtract \(99^{\circ}\) from both sides of the equation \(\angle a = 180^{\circ}-99^{\circ}\)

$$
LATEXBLOCK0
$$

Answer:

$81$