00:01
Okay, so we want to calculate the perimeter of parallelogram a, b, c, d.
00:07
The first thing i notice is that we have two opposite sides that are given, and opposite sides of a parallelogram are always equal.
00:15
So this 5x minus 18 is equal to 2x plus 12.
00:20
So let's figure out what that x is.
00:22
That's going to help us find the perimeter.
00:24
We'll subtract 2x from both sides.
00:27
That gives me 3x.
00:29
And then i can add 18 on both sides, and that'll give me 3x is equal to 30, or the x is equal to 10.
00:39
All right, now having that x equal to 10 is important, because now i can figure out what each side length is...