Question

Find the values of x and y .

a. x=73.3, y=15.3
b. x=73.3, y=20.7
c. x=100, y=10
d. x=100, y=26

Answer 1

Alternate exterior angles are equal.
Therefore,
2x - 70 = x + 30
2x - x = 30 + 70
x = 100

Angles on a straight line are supplementary (equals 180 degrees)
Therefore,
2x - 70 + 5y = 180
2(100) - 70 + 5y = 180
200 - 70 + 5y = 180
5y = 180 - 130 = 50
y = 50/5 = 10
y = 10

x = 100, y = 10

Answer 2

x = ?, y = ?;
2 x - 70° = x + 30°
2 x - x = 30° + 70°
x = 100°
x + 30° + 5 y = 180°
130° + 5 y = 180°
5 y = 180° - 130°
5 y = 50°
y = 50° : 5
y = 10°
Answer: C ) x = 100, y = 10