body{margin:0;} noscript{z-index: 10000; position: fixed; display: block; height: 100%; width: 100%; background: #fff;} noscript .fa{font-size: 40px; display:block; color: #daa520;} noscript div{margin-top: 6%; padding-left: 20px; padding-right: 20px; text-align: center;} ! You must have JavaScript enabled to use this site.

Dashboard

MH

McGraw Hill Integrated II, 2012 View details

6. Trapezoids and Kites

Continue to next subchapter

Exercise 39 Page 528

If a quadrilateral is an isosceles trapezoid, then each pair of leg angles is supplementary.

70

Practice makes perfect

We want to find the measure of ∠ QRS in the given isosceles trapezoid. Let's start from drawing the graph.

We are given that m∠ PQR = 110. Recall that in isosceles trapezoid the leg angles are supplementary. Therefore angles ∠ PQR and ∠ QRS are supplementary, so their measures meet the equation. m∠ PQR + m∠ QRS=180 Let's solve it to find the m∠ QRS.

m∠ PQR + m∠ QRS=180

Substitute

m∠ PQR= 110

110+m∠ QRS =180

SubEqn

LHS-110=RHS-110

m∠ QRS=70

We found that m∠ QRS=70.