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3 years ago

A rectangle is 5 cm wider than twice its length. If the perimeter of the rectangle is 70 cm, then what is the area?

Mathematics

2 answers:

kifflom [539]3 years ago

6 0

Step-by-step explanation:

The dimensions of the rectangle are two unknowns: The length "l" and the width "w"

The perimeter of a rectangle is found as P = 2*l + 2*w

We also know that the length is 5cm more than twice the width. l = 2*w + 5

These two equations gives us a system of linear equations.

P = 2*l + 2*w

l = 2*w + 5

We can use substitution to replace the "l" in the first equation with 2*w + 5

P = 2*(2*w + 5) + 2*w

P = 4*w + 10 + 2*w

P = 6*w + 10

we know the perimeter is 70

70 = 6* w + 10

subtract 10 from both sides

60 = 6* w

w = 10

Now that we know the width, we can find the length by substituting 10 for "w" in the second equation.

l = 2* 10 + 5

l = 20 +5

l = 25

the dimentions of the rectangle are 25cm x 10 cm

HACTEHA [7]3 years ago

6 0

Answer:

Step-by-step explanation:

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Answer:

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Step-by-step explanation:

step 1

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step 3

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$A=(81\pi-81)\ in^2$

simplify

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