the length of rectangle exceeds its breadth by 4 cm if the length and breadth that each increased by 3 cm the area of new rectangle will be 81 cm square more than that of given rectangle find dimension of the rectangle
SDMKJ:
let length of a rectangle be x. so, breadth= x+4.
if length = x+3 then breadth = x+7
area of the previous rectangle= l*b= x(x+4)= x^2+4x
area of the new rectangle=(x+3)(x+7)= x^2+10x+21
x^2+10x+21= x^2+4x+81. [as area of the new rectangle is equal to the sum of 81 and area of the previous rectangle
after solving it; length=x= 10 and breadth= 14
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LET LENGTH BE X
THEN,
BREADTH = X-4
AREA OF THIS TRIANGLE = X(X-4) = (X²-4X)
NOW,
NEW LENGTH = X+3
NEW BREADTH = X-4+3 = X-1
NEW AREA = (X+3)(X-1) = X²+2X-3
QUESTION IS SAYING THAT NEW AREA IS GREATER THAN REAL AREA BY 81 CM².
SO,
X²+2X-3 - (X²-4X) = 81
X²+2X-3-X²+4X = 81
6X-3 = 81
6X = 84
X = 14
DIMENSIONS OF ACTUAL TRIANGLE IS 14 CM IN LENGTH AND 10 CM IN BREADTH.
PLZ MARK IT AS BRAINLIEST ANSWER AND DROP A ♥
THEN,
BREADTH = X-4
AREA OF THIS TRIANGLE = X(X-4) = (X²-4X)
NOW,
NEW LENGTH = X+3
NEW BREADTH = X-4+3 = X-1
NEW AREA = (X+3)(X-1) = X²+2X-3
QUESTION IS SAYING THAT NEW AREA IS GREATER THAN REAL AREA BY 81 CM².
SO,
X²+2X-3 - (X²-4X) = 81
X²+2X-3-X²+4X = 81
6X-3 = 81
6X = 84
X = 14
DIMENSIONS OF ACTUAL TRIANGLE IS 14 CM IN LENGTH AND 10 CM IN BREADTH.
PLZ MARK IT AS BRAINLIEST ANSWER AND DROP A ♥
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