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The area of ​​a rectangle is 168 cm^2. The rectangle has a perimeter of 52 cm. What are the dimensions of the quadrilateral?

1 Answer

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Answer:

12 cm by 14 cm

Explanation:

The area is given by ...

A = LW

The perimeter is given by ...

P = 2(L +W)

Substituting the given values, we have ...

168 = LW

52 = 2(L +W)

The second equation can be used to find an expression for L:

26 = L +W . . . . . divide by 2

L = 26 -W . . . . . subtract W

Using this in the first equation, we have ...

168 = (26 -W)(W)

W² -26W +168 = 0

Factors of 168 are ...

168 = (-1)(-168) = (-2)(-84) = (-3)(-56) = (-4)(-42) = (-6)(-28) = (-7)(-24)

= (-8)(-21) = (-12)(-14)

Only the last factor pair (-12, -14) has a sum of -26, so the equation factors as ...

(W -12)(W -14) = 0

Solutions are W=12, and W=14. The corresponding values of L are 14 and 12.

The quadrilateral has dimensions of 12 cm and 14 cm.

The area of ​​a rectangle is 168 cm^2. The rectangle has a perimeter of 52 cm. What-example-1
User Jujuleder
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