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Find the area of a rectangle whose sides are (4x+1) cm and (2x-5) cm. A. (4x^2 - 19x - 5) cm² B. (8x^2 - 38x - 5) cm² C. (8x^2 - 19x - 5) cm² D. (4x^2 - 38x - 5) cm²

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User Amosmos
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Final answer:

The area of a rectangle with sides (4x+1) cm and (2x-5) cm is calculated by multiplication, applying the FOIL method, with the final formula being (8x² - 18x - 5) cm².

Step-by-step explanation:

To find the area of a rectangle, we need to multiply the length by the width. In this case, the length of the rectangle is (4x+1)cm and the width is (2x-5)cm.

When we multiply these two polynomials, we apply the distributive property of multiplication over addition, also known as FOIL method (First, Outer, Inner, Last):

  • First, multiply the first terms in each binomial: (4x * 2x) = 8x²
  • Outer, multiply the outer terms in the product: (4x * -5) = -20x
  • Inner, multiply the inner terms: (1 * 2x) = 2x
  • Last, multiply the last terms: (1 * -5) = -5

Combine like terms (-20x and 2x) to get -18x. So, the area of the rectangle is A = (8x² - 18x - 5) cm², which is not in the provided options.

Learn more about Area of a Rectangle

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