Point b is the midpoint of ac .ab=2x and ac=3x+20 what is the value of x

We have a segment AC and B is in the middle. So AB + BC = AC because the segment is in pieces. Because B is a midpoint, AB = BC. We now have

AB + BC = AC sum of a segment is sum of its pieces

AB + AB = AC B is the midpoint, so AB = BC

2x + 2x = 3x + 20 putting in for AB (twice!) and AC

4x = 3x + 20 collect like terms

x = 20 subtract 3x on both sides.

So x = 20

1. d.90

2. e. none of these (80)

3. a. 0

4. b. 6

5. e. none of these (10)

6. a. 5