math

A parallelogram has an area of 8x^2 - 2x -45. The height of the parallelogram is 4x + 9. I know the formula for a parallelogram is A=bh. Please work and explain how I get the length of the base of the parallelogram. Thanks

  1. 0
  2. 9
asked by Jane
  1. since a = bh and they give you a polynomial for a and h, you have to expect that b = a/h and (4x+9) divides (8x^2 - 2x -45)

    In fact, 8x^2 - 2x -45 = (4x+9)(2x-5)

    so, b = 2x-5

    If they had given you numbers, you'd have had no trouble doing the division. Don't be confused by their efforts to cloak the underlying simplicity of the question.

    posted by Steve
  2. Factor(unfoil) the area to get:
    (2x-5)* (4x+9). When you divide that by the height, the result is the length of the base: (2x-5)
    Not sure if you're solving for x, but I don't think that there's enough information. Let me know if this helps you!

    posted by Wayne

Respond to this Question

First Name

Your Response

Similar Questions

  1. Math

    A square and a parallelogram have the same area. If a side of the square is 40m and the height of the parallelogram is 20m, find the length of the corresponding base of the parallelogram.
  2. Math

    1) If the height of a parallelogram is 27.3 m and the base is 6.3 m, what is the area of the parallelogram? 2) If the base of a rectangle is 27.4 mm and the area is 420.92 mm2, what is the height of the rectangle? 3) What is the
  3. math

    parallelogram A is similar to Parallelogram B. If the area of parallelogram b is 162 square units, what is the area of parallelogram A?
  4. geometry theorems

    I have six questions which will be on a test two weeks from now, and I do not understand. Help me find out these theorems for the blanks. 1. If one pair of consecutive sides of a parallelogram are congruent, then the parallelogram
  5. Math

    The formula A=bh is used to find the area of a parallelogram. If the base of a parallelogram is double and its height is doubled, how does this affect the area.
  6. math

    a square has side length of 6 inches. a parallelogram has a base of 6 inches. the area of the square is equal to the area of the parallelogram what is the height of the parallelogram?
  7. Math

    in the figure given below, area of parallelogram ABCD is 29 square centimeters.calculate the height of parallelogram ABEF if AB=5.8.
  8. Geometry

    If the length of the base of a parallelogram is decreased by 30%and the height is increased by 20% what Is the percent decrease in the area of the parallelogram
  9. math

    Please help! The area of a parallelogram is ( x^2 + x - 12) and the length of its base is ( x +4). what is the height of the parallelogram?
  10. math

    The base of a rectangle is 2cm greater than its height. Find the base and the height of the parallelogram if the area of the parallelogram is 120 cm2. Can this be shown as a quadratic and factored?

More Similar Questions