Question

Please add a solution

Answer 1

x=120°

Explanation:

The sum of the interior angles of a triangle is equal to 180°, so 70+50+a=180

Solve

120+a=180

a=180-120

a=60

a is the angle opposite the "?"

We know that supplementary angles(angles on a straight line) add up to 180°, so 60 + ? = 180

60+x=180

x=180-60

x=120

Answer 2

D) x = 120°

Explanation:

An exterior angle of a triangle is an angle that is outside the triangle and formed by one side of the triangle and the extension of an adjacent side. The measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles.

Using this:

we can say that

m∠STU + m∠TSU = m∠TUY

Substitute the given values and simplifying it:

50° + 70° = x

120° = x

Therefore answer is:

D) x = 120°