Geometrymedium · Past Paper
Two parallel lines are cut by a transversal. If one co-interior angle is (3x + 20) and the other is (2x + 10), find x.
A15
B30
C50
D70
✓ Correct Answer: B — 30
(3x + 20) + (2x + 10) = 180; 5x + 30 = 180; 5x = 150; x = 30.
Share this question
More from Geometry
- Calculate the value of x if (5x - 5) and (2x + 10) are angles on a straight line.
- Find the measure of an angle such that the sum of its complement and supplement is 200 degrees.
- If the ratio of interior angle to exterior angle of a regular polygon is 5:1, find the number of sides.
- If (1, 2), (4, y), (x, 6), and (3, 5) are vertices of a parallelogram taken in order, then x and y are:
- Find the area of an equilateral triangle with side 6 cm.