Question

The product of two consecutive integers is 72. The equation x(x + 1) = 72 represents the situation, where x represents the smaller integer. Which equation can be factored and solved for the smaller integer?

x2 + x – 72 = 0
x2 + x + 72 = 0
x2 + 2x – 72 = 0
x2 + 2x + 72 = 0

Answer 1

x(x + 1) = 72

x² + x = 72

x² + x - 72 = 0

The first option from the top.

Answer 2

x(x + 1) = 72
Expanding the brackets, we get:

`x^(2)+x=72`
Subtracting 72 from both sides, gives:

`x^(2)+x-72=0`
This is the required equation to be factored and solved .