Answer:
c This is the direct variation
Step-by-step explanation:
The equation for direct variation is y= kx
Solving this for k
y/x =k
So y/x must be a constant
a. 9/3 =3
2/7 does not =3 so this is not a direct variation
b 1/2 = .5
-3/6 = -.5
This is not the same so this is not a direct variation
c. 27/9 =3
18/6 =3
9/3 =3
This is a direct variation with a constant of 3
d 5/-7 = -5/7
1/-3 = -1/3
This is not the same so this is not a direct variation
Longer leg = x + 4
Shorter leg = x
Hypotenuse = x + 8
Using Pythagorean Theorem:
a^2 + b^2 = c^2
(x + 4)^2 + x^2 = (x + 8)^2
x^2 + 8x + 16 + x^2 = x^2 + 16x + 64
2x^2 + 8x + 16 = x^2 + 16x + 64
2x^2 +8x = x^2 + 16x + 48
2x^2 - 8x = x^2 + 48
x^2 - 8x = 48
x^2 - 8x - 48 = 0
You can complete the square from here or use the quadratic formula.
Completing the square:
x^2 - 8x = 48
x^2 - 8x + (-8/2)^2 = 48 + (-8/2)^2
x^2 - 8x + 16 = 48 + 16
(x - 4)(x - 4) = 64 or (x - 4)^2 = 64
x - 4 = +√64 OR x - 4 = -√64
x - 4 = +8 OR x - 4 = -8
x = 12 OR x = -4
However, you can't use negative 4 as a length because your length needs to be a positive.
So x will be 12.
Shorter leg: 12
Longer leg: 12 + 4
Hypotenuse: 12 + 8
Answer:
The general formula for the total surface area of a regular pyramid is T. S. A. =12pl+B where p represents the perimeter of the base, l the slant height and B the area of the base.
The minimum value is the lowest point of a graphed line. The would be the bottom of the "U" shape.
Looking at the graph you can see that the bottom of the U is touching the horizontal line at x = -5.5, so this would be the minimum value.
The lowest part of the line is at -5.5
I believe the answer is D
Because 24x4 is 96