Question

1. look at the figure. find bc.

18
15
16
8

Explanation:

Step1: Use the property of congruent triangles

Since the line \(AC\) is the perpendicular bisector of \(BD\) (indicated by the right - angle and the equal segments on \(BD\)), \(\triangle ABC\cong\triangle ADC\) (by the Hypotenuse - Leg congruence criterion for right - triangles, as \(AB = AD = 15\) is wrong, actually \(CD=18\) and \(BD\) is bisected into two segments of length \(8\)). Wait, no, more accurately, because \(AC\) is the perpendicular bisector of \(BD\), \(BC = CD\) (any point on the perpendicular bisector of a segment is equidistant from the endpoints of the segment).

Answer:

18