Question

HELP PLEASE!

What is the reason for Statement 7 of the two-column proof?

A) Angle Addition Postulate

B) Linear Pair Postulate

C) Ruler Postulate

D) Angle Congruence Postulate


Given: ∠A and ∠B are supplementary. m∠A=90°

Prove: ∠A≅∠B

Answer 1

1. and are supplementary Given

2. Def of supplementary angles

3. Given

4. Substitution property of Equality

5. Subtraction property of Equality

6. Substitution property of Equality

7. Angle congruence postulate

When the measures of two angles are equal, then the angles are congruent by Angle congruence postulate.

Explanation:

Answer 2

Statements Reason

1.
`\angle A` and
`\angle B` are supplementary Given

2.
`m \angle A + m \angle B = 180^\circ` Def of supplementary angles

3.
`m \angle A = 90^\circ` Given

4.
`90^\circ + m \angle B = 180^\circ` Substitution property of Equality

5.
`m \angle B = 90^\circ` Subtraction property of Equality

6.
`m \angle A = m \angle B` Substitution property of Equality

7.
`\angle A \cong \angle B` Angle congruence postulate

When the measures of two angles are equal, then the angles are congruent by Angle congruence postulate.