Quiz (1 point)
Prove that:
m∠XBC = 90
The following properties may be helpful:
- m∠ABC = m∠CBA
- if m∠ABC = 180, then ∠ABX and ∠XBC are supplementary
- if ∠ABC and ∠DEF are supplementary, then (m∠ABC) + (m∠DEF) = 180
if the following are true:
- a = b
- a = c
then b = c
if the following are true:
- a + b = c
- a = d
then d + b = c
if 90 + a = 180, then a = 90
Please write your proof in the table below. Each row should contain one claim. The last claim is the statement that you are trying to prove.