Answer:
Quadrilateral ABCD is not a square. The product of slopes of its diagonals is not -1.
Step-by-step explanation:
Point A is (-4,6)
Point B is (-12,-12)
Point C is (6,-18)
Point D is (13,-1)
Given that the diagonals of a square are perpendicular to each other;
We know that the product of slopes of two perpendicular lines is -1.
So, slope(m) of AC × slope(m) of BD should be equal to -1.
Slope of AC = (Change in y-axis) ÷ (Change in x-axis) = (-18 - 6) ÷ (6 - -4) = -24/10 = -2.4
Slope of BD = (Change in y-axis) ÷ (Change in x-axis) = (-1 - -12) ÷ (13 - -12) = 11/25 = 0.44
The product of slope of AC and slope of BD = -2.4 × 0.44 = -1.056
Since the product of slope of AC and slope of BD is not -1 hence AC is not perpendicular to BD thus quadrilateral ABCD is not a square.
75 minus 68 equal 7 80 minus 71 equal 9. 7 plus 9 equal 16 boxes
The cream paint is 3/2 of the red, since there are three parts cream for every two parts red. Similarly, the blue paint is 1/2 of the red. Thus, there are 3/2*4=6 liters cream paint and 1/2*4=2 liters blue paint.

7x-y=9
3x-y=5 (multiply by -1 both sides of the equation)
7x-y=9
-3x+y=-5 (now add both equations)
7x-3x-y+y=4
4x=4 (divide by 4 both sides of the equation)
x=1
y=3x-5=3×1-5=-2
y= -2
answer: x=1, y=-2