Question

The measure of AngleRST can be represented by the expression (6x + 12)°.

Three lines extend from point S. The space between lines S R and S U is 78 degrees. The space between lines S U and S T is 3 x minus 12.

What is mAngleRST in degrees?

78°
84°
120°
156°

Answer 1

∠ RST = 120°

Explanation:

∠ RST = ∠ RSU + ∠ UST , substitute values

6x + 12 = 78 + 3x - 12

6x + 12 = 3x + 66 ( subtract 3x from both sides )

3x + 12 = 66 ( subtract 12 from both sides )

3x = 54 ( divide both sides by 3 )

x = 18

Thus

∠ RST = 6x + 12 = 6(18) + 12 = 108 + 12 = 120°

Answer 2

The Answer is: C.120

Trust me it is right.

Good Luck:)