Question

what is the measure of angle x in the figure above?
237°
257°
77°
57°

Explanation:

Step1: Recall the triangle angle - sum property

The sum of the interior angles of a triangle is \(180^{\circ}\). Let the three angles of the triangle be \(A = 39^{\circ}\), \(B=84^{\circ}\), and \(C = x^{\circ}\). Then, according to the formula \(A + B+C=180^{\circ}\).

Step2: Substitute the known values and solve for \(x\)

Substitute \(A = 39\) and \(B = 84\) into the equation \(39 + 84+x=180\). First, calculate \(39 + 84=123\). So the equation becomes \(123+x=180\). Then, use the subtraction property of equality: \(x=180 - 123\).

$$x=57$$

Answer:

\(57^{\circ}\)