Question

What is the measure of the exterior angle of the triangle? A. 23°B. 149°C. 180°D. 31°

Answer 1

The diagram below will be of help

From the image above

We know that the sum of angle in a triangle is 180 degrees

That is

`\begin{gathered} 63+86+y=180 \\ 149+y=180 \\ y=180-149 \\ y=31^(\circ) \end{gathered}`

Now, to find x

We also know that the sum of angle in a straight line is 180 degrees

That is

`y+x=180`

We now solve for x

`\begin{gathered} x=180-y \\ x=180-31 \\ x=149^(\circ) \end{gathered}`

Therefore, the value of x = 149 degrees

Option B