We assume the first rectangle measures x cm wide. Then by given details it is 4x cm long .Then its algebraic area = 4x^2 cm^2. (1)
By the given facts the second rectangle measures 4x+5cm long and x+2cm wide. Therefore its area algebraically = (4x+5)(x+2) cm^2 (2)
By the given facts,the ralation between the areas of rectangles is that the area of second rectangle is greater than that of the first by 270 cm ^2.
Therefore,(2)-(1) gives us: (4x+5)(x+2)-4x^2=270 (3).
So,we have set up the equation of this word probem. Now we solve for x to get the width, x and then the length, 4x of the original rectangle from the equation ,(3):
4x^2+(4x)(2)+5x+10-4x^2=270
13x+10=270
13x=270-10
13x=260
13x/13=260/13
x=20cm, width of the original rectangle
4x=80cm, length of the original rectangle.
Tally:
Area of the first(original) rectangle =80*20=1600cm^2
Area of the 2nd rectangle:(80+5)(20+2)=85*22=1870.
1870-1600=270. So, the fact that the 2nd rectangle is greater by 270cm^2 in area is verified.
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