Question

orlando is measuring the angles of a triangle. he measures the first two angles and gets 30° and 70°. what should be the measure of the third angle? a 50° b 80° c 100° d 260°

Explanation:

Step1: Recall the sum of angles in a triangle

The sum of the interior angles of a triangle is \(180^{\circ}\).

Step2: Set up the equation

Let the third - angle be \(x\). Then \(x + 30^{\circ}+70^{\circ}=180^{\circ}\).

Step3: Solve for \(x\)

Simplify the left - hand side of the equation: \(x+(30 + 70)^{\circ}=180^{\circ}\), so \(x + 100^{\circ}=180^{\circ}\). Subtract \(100^{\circ}\) from both sides: \(x=180^{\circ}-100^{\circ}\).

Answer:

B. \(80^{\circ}\)