Big Ideas Math Geometry, 2014
BI
Big Ideas Math Geometry, 2014 View details
5. Measuring and Constructing Angles
Continue to next subchapter

Exercise 36 Page 45

When an angle is bisected, it is cut exactly in half.

m∠ PQS=59.5^(∘)
m∠ RQS=59.5^(∘)

Practice makes perfect

The expression m∠ PQS indicates the measure of the angle between rays QP and QS. Similarly, the expression m∠ RQS indicates the measure of the angle between rays QR and QS. We are also told that QS bisects ∠ PQR. This means that it cuts the angle exactly in half.

Looking at the figures, we can see that m∠ PQR is equal to the sum of m∠ PQS and m∠ RQS. We can form an equation to solve for the missing angles using the given measure and the fact that the two angles created by the bisector are equal to one another.
m∠ PQS+m∠ RQS=m∠ PQR
m∠ PQS+ m∠ PQS=m∠ PQR
m∠ PQS+m∠ PQS= 119
2m∠ PQS=119
m∠ PQS=59.5
Finally, since m∠ RQS is equal to m∠ PQS, we can summarize what we found. m∠ PQS&=59.5^(∘) m∠ RQS&=59.5^(∘)