Answer:
B. 6,-6
Step-by-step explanation:
X^2 + 12 = 48
Subtract 12 from each side
X^2 + 12-12 = 48-12
X^2 = 36
Take the square root of each side
sqrt(X^2 ) = sqrt(36)
X = ±6
Answer:a
Step-by-step explanation:
When you cut along the diagonal, a right triangle is formed where the hypotenuse is the diagonal and the legs are the length and width of the rectangle (10 and 15 in this case)
Now use the pythagorean theorem to solve
10^2+15^2=325=c^2
c= approx 18.02775=length of the diagonal
Answer:
40 ft
Step-by-step explanation:
Let x represent the length in feet of the fourth side. Then the sides perpendicular to the barn wall will have length 800/x, and the total cost of the fence will be ...
cost = $5 × (x + 2·800/x)
The derivative of cost with respect to x will be zero when the cost is a minimum:
d(cost)/dx = 5 -8000/x^2 = 0
5x^2 = 8000 . . . . . multiply by x^2, add 8000
x = √1600 = 40 . . . . feet . . . . . . divide by 5, take the square root
The length of the fourth side should be 40 feet.
