Question

Point B is the midpoint of AC. AB=3x and AC=5x+21 . What is the value of x?

Answer 1

`x=21`

Explanation:

We have been given that point B is the midpoint of AC. This means AB will be equal to BC and AC will be two times AC.

`AC=AB+BC..(1)`

`AB=BC..(2)`

Using substitution, we will get:

`AC=AB+AB`

`AC=2AB`

Substitute given values.

`5x+21=2(3x)`

`5x+21=6x`

Switch sides:

`6x=5x+21`

`6x-5x=5x-5x+21`

`x=21`

Therefore, the value of x is 21.