Geometrymedium · Past Paper
Find the value of x if (2x + 10) and (3x - 40) are vertically opposite angles.
A10
B30
C50
D70
✓ Correct Answer: C — 50
Vertically opposite angles are equal: 2x + 10 = 3x - 40; 10 + 40 = 3x - 2x; x = 50.
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