Question

in the figure below, l || m. find x.

Explanation:

Step1: Use angle - sum property of a triangle

The sum of interior angles of a triangle is 180°. Let the third - angle of the triangle be \(y\). So, \(y+65^{\circ}+60^{\circ}=180^{\circ}\).
\[y = 180^{\circ}-(65^{\circ}+60^{\circ})=180^{\circ}-125^{\circ}=55^{\circ}\]

Step2: Use property of alternate interior angles

Since \(l\parallel m\), \(x\) and \(y\) are alternate interior angles. Alternate interior angles formed by two parallel lines and a transversal are equal. So \(x = y\).

Answer:

55