Answer:
I added a picture, with the answers. I hope it’s good.
Step-by-step explanation:
4x + 89.95 = 628.35 <== ur equation
4x = 628.35 - 89.95
4x = 538.40
x = 538.40 / 4
x = 134.60 <== the cost for each cavity filling
Answer: I’m
Step-by-step explanation: I’d not knkw
<span>Let x = first number
Let y = second number
x + y = 4
x * y = (-12)
Solve the first equation for x.
x = 4 - y
Now substitute this value of x into the second equation.
(4 - y) * y = (-12)
4y - y² = (-12)
y² - 4y - 12 = 0
(y + 2) * (y - 6) = 0
Now set both polynomials equal to zero
y + 2 = 0
y = -2
y - 6 = 0
y = 6
If you substituted these two values for y into either equation and solve for x, you would get the combination of 6 and -2
Hope I was able to help you! :)
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Answer:
Step-by-step explanation:
The the area of the rectangular pen be A = LW
L is the length
W is the width
Given
A = 3136ft²
3136 = LW..........1
Given the perimeter P = 2L+2W....... 2
From 1; L = 3136/W
Substitute into 2
P = 2(3136/W)+2W
P = 6272/W + 2W
In order to minimize the amount of material needed, then dP/dW = 0
dP/dW = -6272/W² + 2
0 = -6272/W² + 2
6272/W² = 2
cross multiply
6272 = 2W²
W² = 3136
W = √3136
W = 56ft
Since A = LW
3136 = 56L
L = 3136/56
L = 56ft
Hence the dimensions of the rectangular pen that minimize the amount of material needed is 56ft by 56ft
