Page 135 - Math Course 3 (Book 2)

Proportional Parts of Triangles

Congruent Segments
To find y:

8
The segments with lengths 5y and y + 7 are
3
congruent since parallel lines that cut off 4a – 5 3b
congruent segments on one transversal cut off
congruent segments on every transversal. 5
3a + 6 b + 2
3
8
5y = y + 7 Equal lengths
3
Multiply each side by 3 to
15y = 8y + 21
eliminate the denominator.
Find a.
7y = 21 Subtract 8y from each side. 11
A. B. 1
y = 3 Divide each side by 7. 7
C. 11 D. 7

Answer
Answer x = 6; y = 3
Find b.
A. 0.5 B. 1.5

C. –6 D. 1
Your Turn! Answer

Midsegment of a Triangle
Triangle UXY has vertices U(–3, 1), X(3, 3) and y X
Y(5, –7). WZ is a midsegment of △UXY. Find the W (3, 3)
coordinates of W and Z.
(–3, 1)
U
A. W (0, 1), Z (1, –3)
B. W (0, 2), Z (2, –3)
C. W (0, 3), Z (2, –3) O x
D. W (0, 2), Z (1, –3) Z

Answer
(5, –7)
Y

Triangle UXY has vertices U(–3, 1), X(3, 3) and Triangle UXY has vertices U(–3, 1), X(3, 3) and
Y(5, –7). WZ is a midsegment of △UXY. Y(5, –7). WZ is a midsegment of △UXY.
1
Is WZ || XY? Is WZ = XY?
2
A. Yes A. Yes
B. No B. No

Answer Answer

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