A cube has side length x. One side of the cube is increased by 4 inches, and another side is doubled. The volume of the new rectangula

Question

A cube has side length x. One side of the cube is increased by 4 inches, and another side is doubled. The volume of
the new rectangular prism is 450 cubic inches. The equation 2y3+8×2-450 can be used to find x. What was the side
length of the original cube? Use a graphing calculator and a system of equations to find the answer.
O 4 inches
O5 inches
O 9 inches
O 10 inches

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Amity 5 years 2021-07-31T12:22:42+00:00 2 Answers 234 views 0

Answers ( )

  1. Ladonna
    0
    2021-07-31T12:24:10+00:00
    Reply

    Answer:

    Step-by-step explanation:

    new dimensions of prism: x by (x+4) by (2x).

    volume = x(x+4)(2x) = 2x³ + 8x²

    2x³ + 8x² = 450

    2x³ + 8x² – 450 = 0

    x³ + 4x² – 225 = 0

    x = 5 in

  2. Edana
    0
    2021-07-31T12:24:11+00:00
    Reply

    9514 1404 393

    Answer:

      (b)  5 inches

    Step-by-step explanation:

    A graphing calculator makes short work of the problem. No system of equations is needed.

    The volume of the new prism is …

      V = LWH

      450 = x(x+4)(2x)

      x(2x)(x+4) -450 = 0 . . . . . equation for graphing

    The only real solution is x = 5.

    The side length of the original cube was 5 inches.

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Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )