# Rectangle - sides 3

If in the rectangle ABCD we enlarge the side a by 5 cm and decrease the side b by 2 cm, the rectangle area will be reduced by 5 cm². When we decrease the length of the side a by 4 cm and and at the same time we increase the length of side b by 3 cm we increases the area of the original rectangle by 5 cm².

Calculate the length of the sides of the rectangle ABCD.

Result

a =  15 cm
b =  7 cm

#### Solution:

(a+5)*(b-2) = a*b - 5
(a-4)*(b+3) = a*b + 5

2a-5b = -5
3a-4b = 17

a = 15
b = 7

Calculated by our linear equations calculator.

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