Answer:
Must understand distance and slope formula first:
slope y_2-y_1/x_2-x_1
distance d=√((x_2-x_1)²+(y_2-y_1)²)
(Just search up the formulas if this isn't clear)
Step-by-step explanation:
For #13 take two points and put them in the distance formula remember (#,#) the first # is 'x' the second # is the 'y' in a point.
then you could simply type all that in a calculator and a single number should pop up indicating one of the lines (doesn't matter the #) then do the same for the second points (cuz you used two already you have two left) If the number is same as the first two points it's a pallelagram. (I tested it out got 7.07...)
For the slope you're doing something similar to the distance formula, you're filling out two sets of points into the slope formula if they come out the same # it's parallel.
