Question

The difference of the square of a number and three times the sum of the number and 7 is more than the product of that number and 15.

Select the inequality that can be used to determine the unknown number.

A.
x2 - 3x - 21 > 15x
B.
x2 - 3x + 21 > 15 + x
C.
x2 - 3x + 7 ≥ 15x
D.
x2 + 3x ≥ 15 + x

Answer 1

A

Explanation:

The question stated that the difference of the square of a number and three times the sum of the number and 7 (x^2-3 (x+7))is more than the product of that number and 15 (15x)

So x^2- 3(x+7)>15(x)= x^2 -3x +21>15x