Question

If B is the midpoint of AC and AC=8x-20 find BC

Answer 1

we are given

B is the midpoint of AC

so,

$AB=BC$

$AC=AB+BC$

$AC=BC+BC$

$AC=2BC$

now, we are given

AC=8x-20

so, we can plug it

$8x-20=2BC$

we can divide both sides by 2

and we get

$BC=4x-10$.............Answer

Answer 2

We know that AC=8x-20 and B is the mid-point of AC

⇒ AB = BC = $\frac{AC}{2}$

⇒ BC = $\frac{8x-20}{2}$

⇒ BC = 4x-10