Question

A. ½
B. -¼
C. 2
D. -2
E. -4

Answer 1

D -2

Explanation:

any triangle inscribed into a half-circle is a right-angled triangle.

that means the triangle angle at B is 90°.

so, BC and AB are always perpendicular to each other (90° crossing angle).

remember, when the original slope is y/x, then the perpendicular slope is -x/y.

so, in our case the original slope of BC is 1/2.

therefore, the perpendicular slope (the slope of AB) is then

-2/1 = -2