Find the value of x. Given: RS=ST, m∠RST=7x-54, m∠STU=8x

S

Δ_U

RT

a. 14

b. 152

c. 16

d. 19

Given:

∠STU = 8x

∠RST = (7x - 54)

Solution:

∠SRT + ∠RST = 8x (exterior angle is sum of interior angles)

∠SRT + (7x - 54) = 8x

∠SRT = 8x - (7x - 54)

= x + 54

∠STR + ∠STU = 180 is the linear pair

x + 54 + 8x = 180

9x = 126

x = 14