Question

Find the measurement of the third angle of a triangle with two angles measuring 18° and 82°. Please show your work.

Answer 1

A triangle is 180* so you substructure 18 and 82 from 180. Which is 80*

Answer 2

The sum of the measures of the interior angles of a triangle add up to 180 degrees.

Since you have two angles of the triangle, add them up to equal 180 in an equation and solve for x (the third angle).

18 + 82 + x = 180

Combine like terms.

100 + x = 180

Subtract 100 from both sides.

x = 80

The third angle of the triangle is 80 degrees.