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. What inequality can be used to determine the unknown number?

Answer 1

Step-by-step explanation:

a number = x

square of a number =

${x}^{2}$

the times the number = 3x

three times the sum of the number and seven = 3( x+7)

difference of the square of a number and three times the sum of the number =

${x}^{2} - 3(x + 7)$

product of that number and 15 =

$x \times 15$

$15x$

that is,

${x}^{2} - 3(x + 7) > x \times 15$

${x}^{2} - 3x - 21 > x \times 15$

${x}^{2} - 3x - 21 > 15x$