180 ¼xþ 2 xþ 2 x 20
180 ¼ 5 x 20
180 þ 20 ¼ 5 x 20 þ 20
200 ¼ 5 x
200
5
¼
51 x
51
408 ¼x
2 x¼ 2 ð 40 Þ¼ 808
2 x 20 ¼ 2 ð 40 Þ 20 ¼ 608
The measures of the three angles are 40 8 ,60 8 , and 80 8.
5 : Letx¼the measure of one angle
xþ 258 ¼the measure of the other angle
xþxþ 258 ¼ 90 25
xþxþ 25 25 ¼ 90 25
2 x¼ 65
21 x
21
¼
65
2
x¼ 32 : 58
xþ 258 ¼ 32 : 5 þ 25 ¼ 57 : 58
6 : Letx¼the measure of one angle
2 xþ 30 ¼the measure of the second angle
xþ 2 xþ 30 ¼the measure of the third angle
248 LESSON 20 Word Problems in Geometry