Solve for x: co-interior angles
Write an equation from the angle relationship: equal angles are set equal, co-interior angles add to 180°. Then solve for x.
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Two parallel lines are cut by a transversal. Two co-interior angles measure (4x + 8)° and (4x + 20)°. Find x.
Answer: 19
Two parallel lines are cut by a transversal. Two co-interior angles measure (3x + 19)° and (5x + 49)°. Find x.
Answer: 14
Two parallel lines are cut by a transversal. Two co-interior angles measure (4x + 4)° and (5x + 59)°. Find x.
Answer: 13
Tip: Write an equation from the angle relationship: equal angles are set equal, co-interior angles add to 180°. Then solve for x.
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