The coordinates of rectangle wxyz are w(−4, 2), x(3, 2), y(3, −4) and z(−4, −4). what is its perimeter?

We know that
perimeter of rectangle=2*[length+width]

we have 
W(−4, 2), X(3, 2), Y(3, −4) and Z(−4, −4)

let
length=distance WX
width=distance XY

step 1 
find the distance WX
d=√[(y2-y1)²+(x2-x1)²]-----> d=√[(2-2)²+(3+4)²]----> d=√49----> d=7 units

step 2
find the distance XY
d=√[(y2-y1)²+(x2-x1)²]-----> d=√[(-4-2)²+(3-3)²]----> d=√36----> d=6 units

step 3
 find the perimeter
perimeter of rectangle=2*[7+6]----> 26 units

the answer is
26 units

see the attached figure