Question

what is the value of r?
none of these
75
95
85

Explanation:

Step1: Find the interior angle adjacent to \( r^{\circ} \)

The sum of interior angles of a triangle is \( 180^{\circ} \). Let the interior angle adjacent to \( r^{\circ} \) be \( x \). Then \( x=180-(45 + 50)=180 - 95=85^{\circ}\)

Step2: Use the linear - pair relationship

Since \( r \) and \( x \) form a linear pair (\( r+x = 180^{\circ}\)), then \( r=180 - x\). Substitute \( x = 85^{\circ}\) into the equation, we get \( r=180-85 = 95^{\circ}\)

Answer:

95