Question

If anybody answers these questions I will get them brainliest and if somebody else verifies that it is the correct answer I can give you a thanks.

Answer 1

Part (a)

Answer: x^3 + 12x^2 + 47x + 60

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Work Shown:

Let's say we have

• L = length = x+5
• W = width = x+4
• H = height = x+3

To find the volume of the block, we multiply the length width and height.

So,

volume = (length)*(width)*(height)

V = L*W*H

V = LW*(x+3) .... replace H with (x+3)

V = LW*x + LW*3 .... distribute

V = Lx*(W) + 3L*(W)

V = Lx(x+4) + 3L(x+4) .... replace W with x+4

V = Lx^2 + 4Lx + 3Lx + 12L .... distribute

V = Lx^2 + 7Lx + 12L

V = x^2*(L) + 7x*(L) + 12*(L)

V = x^2*(x+5) + 7x*(x+5) + 12*(x+5) .... replace L with x+5

V = x^3 + 5x^2 + 7x^2 + 35x + 12x + 60 .... distribute

V = x^3 + 12x^2 + 47x + 60

x^3 + 12x^2 + 47x + 60 is the polynomial in standard form that represents the volume of the block.

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Part (b)

Answer: 336 cubic feet

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Work Shown:

We can plug x = 3 into the polynomial we found

V = x^3 + 12x^2 + 47x + 60

V = (3)^3 + 12(3)^2 + 47(3) + 60

V = 27 + 12(9) + 47(3) + 60

V = 27 + 108 + 141 + 60

V = 336

Or we could find the volume like this

V = L*W*H

V = (x+5)*(x+4)*(x+3)

V = (3+5)*(3+4)*(3+3)

V = (8)*(7)*(6)

V = 336

Either way, we get the same volume of 336 cubic feet.