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Notice that ∠SQR is an exterior angle to △ QRT, so you can apply the Exterior Angle Theorem.
| Statements | Reasons |
| RQ bisects ∠SRT | Given |
| ∠SRQ ≅ ∠QRT | Definition of angle bisector |
| m∠SRQ = m∠QRT | Definition of congruent angles |
| ∠SQR is exterior to △ QRT | From the diagram |
| m∠SQR > m∠QRT | Exterior Angle Theorem |
| m∠SQR > m∠SRQ | Substitution |
Since RQ bisects ∠SRT we have that ∠SRQ ≅ ∠QRT, which means that m ∠SRQ = m ∠QRT.
Therefore, by applying the Exterior Angle Theorem, we have that m ∠SQR > m ∠QRT but, since m ∠SRQ = m ∠QRT, we obtain that m ∠SQR > m ∠SRQ.
In the following table we summarize the proof we did before.
| Statements | Reasons |
| RQ bisects ∠SRT | Given |
| ∠SRQ ≅ ∠QRT | Definition of angle bisector |
| m∠SRQ = m∠QRT | Definition of congruent angles |
| ∠SQR is exterior to △ QRT | From the diagram |
| m∠SQR > m∠QRT | Exterior Angle Theorem |
| m∠SQR > m∠SRQ | Substitution |