Question

∠A and ∠B are vertical angles. If m∠A=(3x-30)° and m∠B=(2x-9)°,then find the value of x.

Answer 1

x = 21

Explanation:

Vertical angles are congruent, thus

∠ A = ∠ B , substitute values

3x - 30 = 2x - 9 ( subtract 2x from both sides )

x - 30 = - 9 ( add 30 to both sides )

x = 21

Answer 2

Hello there! :)

`\huge\boxed{x = 21}`

Vertical angles are congruent, therefore:

∠A ≅ ∠B

3x - 30 = 2x - 9

Subtract 2x from both sides:

3x - 2x - 30 = 2x - 2x - 9

x - 30 = -9

Add 30 to both sides:

x - 30 + 30 = -9 + 30

x = 21.