Answer: The width is 7 meters. The length is 10 meters.
Step-by-step explanation: Area = Length × width
Length is 2w - 4
Substitute that value for length, then solve for w.
70 = w(2w - 4)
70 = 2w² - 4w reorganize to quadratic equation form
2w² - 4w -70 = 0 These are All even numbers; factor out 2 (divide all by 2)
w² - 2w - 35 = 0 factor this
(w - 7)(w + 5) set each factor = 0 and calculate the value of w.
w+5=0 w= -5 (disregard this one because dimensions of real rectangles can't be negative)
w - 7 = 0 w = 7 <u>The width is 7</u>
Substitute into the original expressions to get the value of Length.
2(7) -4 = L 14 - 4 = L The<u> Length is 10.</u>
Check by substituting into the original equation:
w × 2w -4 = 70
7 × 2(7) -4 = 70
7 × 10 = 70 TRUE!
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