Question

in the diagram right above, HIJK is a rectangle. I mainly need help to find with slope of IJ and KH. I can not figure out coordinates of J and K. Here is image of problem
http://imgur.com/dCTlntx
Thanks :)

Answer 1

What do you know about any two consecutive sides of a rectangle? I mean, what angle is formed by any two consecutive sides of a rectangle?

Answer 2

They are 90 degrees.

Answer 3

What are the measures of angles A, B, C, and D?

Answer 4

Correct.
Since every angle in a rectangle is 90 degrees, that means every angle is a right angle.
That makes any two consecutive sides perpendicular.
Ok so far?

Answer 5

Yup

Answer 6

Now look at your problem.
You know the coordinates of points H and I.
You can find the slope of segment HI, right?

Answer 7

Yes.

Answer 8

Oh I got it.
It would be reciprocal of the HI right ?

Answer 9

The slope, \(m\), of the segment that contains points \((x_1, y_1)\) and \((x_2 , y_2)\) is

\(m = \dfrac{y_2 - y_1}{x_2 - x_1} \)

Answer 10

Once you find the slope of HI, the slopes of the two sides KH and JI is the negative reciprocal of the slope of segment HI.

Answer 11

Oh okay. I got that. Thank you :)

Answer 12

Remember the negative along with the reciprocal.

If a line has slope 3/4, a perpendicular line has slope -4/3.
(Flip the fraction and change the sign.)

Answer 13

Great.
You're welcome.