Question

1. y =

how many degrees in a
straight line??

Explanation:

Step1: Find the adjacent angle of 160°

Since the sum of adjacent angles on a straight line is 180°, the adjacent angle of 160° is \(180 - 160=20\) degrees.

Step2: Find the adjacent angle of 100°

Since the sum of adjacent angles on a straight line is 180°, the adjacent angle of 100° is \(180 - 100 = 80\) degrees.

Step3: Use the triangle - angle sum property

The sum of angles in a triangle is 180°. Let the angle \(y\). Then \(y+20 + 80=180\).

$$y=180-(20 + 80)$$

$$y = 80$$

Answer:

\(80\)