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The area of a rectangle is 28 square inches. The length is 8 more than thrice the width. How do you find the length and the width?

Answer 1

Eva Abramson

Width = #2#
Length = #14#

Length: #L = 3x + 8# Width: #W=x#

Area of Rectangle = #LW# #28 = (3x+8)x# #28 = 3x^2 + 8x# #0 = 3x^2 + 8x - 28# #0 = (3x + 14 )(x - 2)#

#3x + 14 = 0 -> x = -14/3# But Width can't be negative.

#x - 2 = 0 -> x = 2# So Width is #2# and Length is #3(2)+8 = 14#

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Answer 2

Eva Abramson

Let the width be x inches. Then, the length is (3x + 8) inches. Area = length × width 28 = (3x + 8) * x 28 = 3x^2 + 8x 3x^2 + 8x - 28 = 0 Now, solve the quadratic equation to find the value(s) of x. Once you have the value(s) of x, substitute it back to find the length and width.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.