Question

Select the correct answer from each drop-down menu.

CD is perpendicular to AB and passes through point C(5, 12).
If the coordinates of A and B are (-10, -3) and (7, 14), respectively, the x-intercept of CD is ___. The point ____ lies on CD.

Answer 1

y = -x + 17

Explanation:

A(-10,-3)

B(7,14)

C(5,12)

Need line CD perpendicular to AB through C.

Solution:

slope of AB, m1 = (yb-ya) / (xb-xa) = (14- -3) / (7- -10) = 17/17 = 1

Slope of CD, m2 = -1/m1 = -1 / 1 = -1

Line CD through C, using the point slope form

y-yc = m2(x-xc)

y-12 = -1 (x-5)

rearrange

y = -x + 5 + 12

y = -x + 17

Answer 2

x intercept of CD is (17, 0)

Point (-2, 19) lies on CD

Explanation: