A rectangle is 4 times as long as it is Wide. A second rectangle is 5 centimeters longer and 2 centimeters wider than the first. The area of the second rectangle is 530 square centimeters greater than the first. What are the dimensions of the original rectangle?
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original rectangle: x cm wide by 4x cm long...
area of 1st = 4x^2 cm^2
second rectangle:
length = (4x + 5) cm
width = (x + 2) cm
area = (4x + 5)(x + 2) = 4x^2 + 13x + 10 cm^2
this is 530 cm^2 greater than 4x^2
so,
4x^2 + 13x + 10 = 4x^2 + 530
solve for x
13x = 520
x = 40
the first rectangle is:
40 cm wide
160 cm long
area = 6400 cm^2
the second rectangle is:
165 cm long
42 cm wide
area = 6930 cm^2
practice...read your textbook.
area of 1st = 4x^2 cm^2
second rectangle:
length = (4x + 5) cm
width = (x + 2) cm
area = (4x + 5)(x + 2) = 4x^2 + 13x + 10 cm^2
this is 530 cm^2 greater than 4x^2
so,
4x^2 + 13x + 10 = 4x^2 + 530
solve for x
13x = 520
x = 40
the first rectangle is:
40 cm wide
160 cm long
area = 6400 cm^2
the second rectangle is:
165 cm long
42 cm wide
area = 6930 cm^2
practice...read your textbook.
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The first rectangle is x W and 4x L. A1 = x * 4x = 4x^2
The second rectangle is (x + 2) W and (4x + 5) L. A2 = (x + 2)(4x + 5) = 4x^2 + 13x + 10
4x^2 + 13x + 10 = 4x^2 + 530
13x + 10 = 530
13x = 520
x = 40
So the original rectangle is 40 * 160, and it's area is 6400
The second rectangle is 42 * 165, and it's area is 6930, which is 530 greater than the first one.
The second rectangle is (x + 2) W and (4x + 5) L. A2 = (x + 2)(4x + 5) = 4x^2 + 13x + 10
4x^2 + 13x + 10 = 4x^2 + 530
13x + 10 = 530
13x = 520
x = 40
So the original rectangle is 40 * 160, and it's area is 6400
The second rectangle is 42 * 165, and it's area is 6930, which is 530 greater than the first one.
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suppose the original width is x and length 4x
for the 1st rect, area = x * 4x = 4x^2
for the 2nd rect, area = (4x + 5)(x + 2)
now,
(4x + 5)(x + 2) = 530 + 4x^2
=> 4x^2 + 13x + 10 = 530 + 4x^2
=> 13x = 520
=> x = 40
hence the dimensions of the original rect are 40 and 160
for the 1st rect, area = x * 4x = 4x^2
for the 2nd rect, area = (4x + 5)(x + 2)
now,
(4x + 5)(x + 2) = 530 + 4x^2
=> 4x^2 + 13x + 10 = 530 + 4x^2
=> 13x = 520
=> x = 40
hence the dimensions of the original rect are 40 and 160