Question

Segment BDSegment BD is a perpendicular bisector of segment ACsegment AC . AD=8x−15AD=8x−15 and DC=57DC=57 .

What is the value of x?

Answer 1

Since BD is a perpendicular bisector of AC, then ADC forms an isisceles triangle with AD = DC.
Thus 8x - 15 = 57
8x = 57 + 15 = 72
x = 72/8 = 9.