Question

LM=3x+8

MN=2x-5

LN=23

Suppose M is between L and N. Use the Segment
Addition Postulate to solve for the variable. Then find the lengths of LMÆ,
MNÆ, and LNÆ.

Answer 1

LM+MN=23

3x+8+2x-5=23

5x+3=23

5x=23-3=20

x=20/5=4

LM=3x+8=12+8=20units

MN=2x-5=8-5=3units

Answer 2

LM=3X+8

MN=2X-5

LN=23

LN=LM+MN

23=3X+8+2X-5

23=3X+2X+8-5

23=5X+3

23-3=5X+3-3

20=5X

20/5=5X/5

4=X

X=4

Check;

LM=3X+8

3X+8=3(4)+8

3X+8=12+8

3X+8=20

LM=20

MN=2X-5

2X-5=2(4)-5

2X-5=8-5

2X-5=3

MN=3

LM+MN=20+3

LN=23

verified