SOLUTION: the width of a classroom is 4meters less than the length .lts area is 45meters-squared .find the dimensions of a classroom

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Question 1030773: the width of a classroom is 4meters less than the length .lts area is 45meters-squared .find the dimensions of a classroom
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
Make the length = x
Width then = x - 4
Area = Length x Width
45 = x(x - 4)
45 = x^2 - 4x
Reform into ax^2 + bx + c = 0 form:
x^2 - 4x - 45 = 0
Factorize:
(x + 5)(x - 9) = 0
x = 5 = 0
x = -5 (Ignore as -ve value)
x - 9 = 0
x = 9
Length of classroom = 9 meters
Width of classroom = 5 meters.
Hope this helps :-)