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PLEASE HELP

Find the length of the longest side if the area of the rectangle is 28m
2

PLEASE HELP Find the length of the longest side if the area of the rectangle is 28m-example-1
User AlDiablo
by
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1 Answer

4 votes

Answer:

longest side = 7 ft

Explanation:

Area of rectangle = 28 m²

length * width = 28

(x + 3) * x =28

x*x + 3*x = 28

x² + 3x = 28

x² + 3x - 28 = 0

We look for two integers which when subtracted give 3 and when multiplied give (-28). The factors are 7 and (-4)

7 + (-4) = 3 & 7 *(-4) = -28

Rewrite the middle term using the factors.

x² + 7x - 4x -28 = 0

Take out the common factor x from the first and second term &

take out the common factor (-4) from the third and fourth term.

x(x + 7) - 4(x + 7) = 0

(x + 7) (x - 4) = 0

{Ignore x + 7 = 0 as dimensions of rectangle will not be negative}

x - 4 = 0

x = 4

x + 3 = 4 + 3

= 7

Longest side = 7 feet

User Chris Kuklewicz
by
8.3k points