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Maths Exercices
Applications of quadratic equations


Suppose a rectangle has an area of 90m2 and the sides are x+1 and x+2. Find the dimensions of the rectangle.
(x+1)·(x+2)=90
x2+3x+2=90
x2+3x-88=0
(x+11)·(x-8)=0
x+11=0; x=-11
x-8=0; x=8
The sides are 9m and 10m long.

Given three consecutive pairs of natural numbers, we subtract from the square of the greatest number the square of the other two numbers and the result is -84. What are the original numbers?

The numbers in order of smallest to largest are: