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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:

(12, 0)
(15, 0)
(17, 0)
or (19,0).

The point:

(-5, 24)
(-2, 19)
(7, -10)
or (8, 11)

lies on CD.

User Pgrono
by
7.7k points

2 Answers

3 votes

Answer

CD is 17,0

The point -2,19

Explanation:

User Sinane
by
7.6k points
3 votes
The slope of AB is

m=(y_(2)-y_(1))/(x_(2)-x_(1))

=(14-(-3))/(7-(-10))

=(17)/(17)

=1

So the slope of CD is

-(1)/(m)=-(1)/(1)=-1

The equation for CD is then

y=-x+b
We find
b by plugging in the point
(5, 12):

12=-5+b

\rightarrow b=17

\rightarrow y=-x+17

The x-intercept is found by setting
y equal to 0:

0=-x+17

\rightarrow x=17
which gives
(17, 0).

For the second part, we just plug in the different points and see if the equation is true:

(-5, 24)\rightarrow 24=-(-5)+17\rightarrow 24=5+17\rightarrow 24=22
(doesn't work)

(-2, 19)\rightarrow 19=-(-2)+17\rightarrow 19=2+17\rightarrow 19=19
So the answer must be
(-2, 19).
User Justin Ober
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7.9k points