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3 years ago

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A rectangle’s length is 2 units more than twice its width. Its area is 40 square units. The equation w(2w + 2) = 40 can be used

to find w, the width of the rectangle.

2 answers:

antoniya [11.8K]3 years ago

7 0

Answer: Value of w is 4 units and the equation is correct.

Step-by-step explanation:

Let width of a rectangle be 'w'.

Let length of a rectangle be '2w+2'.

Since we have given that

Area of rectangle = 40 square units.

As we know the formula for "Area = Length × Breadth" :

So, it becomes,

$40=w(2w+2)\\\\40=2w^2+2w\\\\20=w^2+w\\\\w^2+w-20=0\\\\w^2+5w-4w-20=0\\\\w(w+5)-4(w+5)=0\\\\(w+5)(w-4)=0\\\\either\ w=-5\ or\ w=4$

But dimension can't be negative.

So, w must be 4 units.

Hence, Value of w is 4 units and the equation is correct.

barxatty [35]3 years ago

5 0

I hope this helps you

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