Eighty-seven decreased by three times a number is greater than one hundred sixty-five

This is the concept of algebra, we are required to find a number, x, such that 87 decreased by three times a number is great than one hundred and sixty-five.

Supposed the number is x, three times the number will be:

3*x=3x

thus;

87-3x≥165

-3x≥165-87

-3x≥78

dividing both sides by - 3 we get:

(-3x) / (-3x) ≥78 / (-3)

x≤-26

This implies that the number is less than or equal to 26