Question

Please help its only A B C D which should equal 105degree to prove that f // g?

Answer 1

Option (4)

Explanation:

From the figure attached,

∠b = 75° [Vertical angles]

If the lines f and g are parallel then,

∠b = ∠c [Corresponding angles]

Therefore, ∠c = 75°

Since m∠c + m∠d = 180° [Supplementary angles]

75° + m∠d = 180°

m∠d = 180° - 75°

m∠d = 105°

Therefore, measure of angle d should be equal to 105° to prove f and g are parallel.

Option (4) will be the answer.