SOLUTION: A rectangle was altered by decreasing its length by 15% and increasing its width by x %. If these alterations increased the area of the rectangle by 19%, what is the value of x?

Question 1043914: A rectangle was altered by decreasing its length by 15% and increasing its width by x %. If these alterations increased the area of the rectangle by 19%, what is the value of x?
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
original rectangle had length l and width w
area is lw
(0.85)l * xw=0.85x lw, which = lw*(1.19)
lw cancels
0.85x=1.19
x=1.19/0.85
x=1.4
x is 40%
---------------
example:
rectangle is 25 x4=100 sq units
length is decreased 15% to 21.25
width is increased 40% to 5.6
21.25*5.6=119, which is a 19% increase

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