Respuesta :
We know that AC=8x-20 and B is the mid-point of AC
⇒ AB = BC = [tex]\frac{AC}{2}[/tex]
⇒ BC = [tex]\frac{8x-20}{2}[/tex]
⇒ BC = 4x-10
we are given
B is the midpoint of AC
so,
[tex]AB=BC[/tex]
[tex]AC=AB+BC[/tex]
[tex]AC=BC+BC[/tex]
[tex]AC=2BC[/tex]
now, we are given
AC=8x-20
so, we can plug it
[tex]8x-20=2BC[/tex]
we can divide both sides by 2
and we get
[tex]BC=4x-10[/tex].............Answer
