Question

what is $mangle1$?
$mangle1=square^{circ}$

Explanation:

Step1: Find the adjacent angle of \(135^{\circ}\)

The adjacent angle of \(135^{\circ}\) is \(180 - 135=45^{\circ}\) (linear - pair of angles: sum to \(180^{\circ}\)).

Step2: Use the triangle - angle - sum theorem

In a triangle, the sum of interior angles is \(180^{\circ}\). Let \(\angle1=x\), we know one angle is \(45^{\circ}\) and another is \(87^{\circ}\). Then \(x + 45+87 = 180\).

$$x=180-(45 + 87)$$

$$x=180 - 132$$

Answer:

\(48\)