A parallelogram has vertices A(0, 4), B(2, 2), C(4, 4), and D(2,6). Is this parallelogram a square? Explain why or why not.

If we take the adjacent side AD and DC  and work out their slopes we get  

AD = (6-4)/(2-0)  = 1 and DC has slope (6-4)/(2-4)  = -1 . This shows that the angle between the 2 lines is 90 degrees so it looks like  this is a square. If you include the slopes  of each adjacent line they are at right angles too.  Now to prove its a square  each line must be of equal length and you'll find this is the case too.

i = 2 / - 5

step-by-step explanation:

evaluation of ( 2 - 4 ) ( p + q ) when p = 2 and q = 5 i, by putting values of p and q,