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3 years ago

The length of a rectangle is 9 cm more then half the width. Find the length of the perimeter is 60cm

Mathematics

1 answer:

stira [4]3 years ago

7 0

length = 1/2 w+9

perimeter= 60 =2(l+w)

substitute in for length

60 = 2(1/2 w +9 +w)

60 = 2 (3/2 w +9)

distribute

60 = 3w + 18

subtract 18 from each side

42 = 3w

divide by 3 on each side

14 = w

length = 1/2 w + 9

length = 1/2 (14) +9

7 + 9

16cm

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Now, to find the lengths of the diagonals,

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