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** This is a 2-pa
1. The length of a rectangle is 4 meters less than
twice its width. The area of the rectangle is
70 m2. Find the dimensions of the rectangle.

1 Answer

9 votes

Answer:

length is 10, width is 7

Explanation:

Area of a rectangle = length * width = lw

Area is known to be 70

length = twice width - 4 = 2w-4 = l

width=w

so A = lw = (2w-4)w = 70

(2w-4)w=70

2w^2-4w=70

2w^2-4w-70=0, divide by 2

w^2 - 2w - 35 = 0, not sure how your class solves these, I see visually

(w-7)(w+5)=0

w=7 or w=-5, -5 makes no sense in the real world (negative length), so w=7

l = 2w-4 = 2(7)-4 = 14-4 = 10

User Shishant
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