Let F be between G and H. Use the Segment Addition Postulate to solve for u. GF = 3u + 21 FH = 7u + 9 GH = 50 A. u = 3 B. u = 7 C. u = 5 D. u = 2

Question

Let F be between G and H. Use the Segment Addition Postulate to solve for u.	GF = 3u + 21	FH = 7u + 9	GH = 50
A. u = 3
B. u = 7
C. u = 5
D. u = 2

Answer 1

Answer: D. u = 2

Solution: GH = GF + FH

50 = (3u + 21) + (7u + 9) Substitution

50 = (3u + 21) + (9 + 7u) Commutative Property of Addition

50 = (3u + 30 + 7u)

50 = (3u + 7u + 30) Commutative Property of Addition

50 = 10u + 30

Subtract 30 from both sides:

20 = 10u

Divide by 10:

u = 2