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the length of a rectangle is 7 cm more than its width and the area is 30 cm find the length, width and the perimeter

User Sam Leach
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1 Answer

11 votes

Answer:

Explanation:

let width=x

length=x+7

x(x+7)=30

x²+7x-30=0

x²+10x-3x-30=0

x(x+10)-3(x+10)=0

(x+10)(x-3)=0

either x=-10 (rejected being negative)

or x=3

width=3 cm

length=3+7=10 cm

Perimeter=2(10+3)=2×13=26 cm

User Ruwan
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