Answer:
x = 12
m∠UTS = 87
m∠TSR = 143
Explanation:
We know that the angles 56, (3 + 7x), and UST, add up to 180, and that UST and (12x - 1) also add up to 180
Therefore we can say UST = 180 - (12x - 1)
and that:
56 + 3 + 7x + (180 - (12x - 1)) = 180
59 + 7x + 180 - 12x + 1 = 180 (combine like terms and distribute negative)
240 - 5x = 180 (subtract 240 from both sides)
-5x = -60 (divide both sides by -5)
x = 12
Therefore,
m∠UTS = 3 + 7(12) = 87
and
m∠TSR = 12(12) - 1 = 143