Question

15. A rectangle has a length of 2x - 1 and a width of 3x + 7. Find the perimeter of this rectangle.

Then find the area of the rectangle.

Answer 1

10x + 12 and 6x² + 11x - 7

Explanation:

The perimeter (P) of a rectangle is calculated as

P = 2l + 2w ( l is length and w is width )

= 2(2x - 1) + 2(3x + 7) ← distribute parenthesis

= 4x - 2 + 6x + 14 ← collect like terms

= 10x + 12

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The area (A) of a rectangle is calculated as

A = lw

= (2x - 1)(3x + 7) ← expand using FOIL

= 6x² + 14x - 3x - 7 ← collect like terms

= 6x² + 11x - 7