Question

What property is used in the second step of solving the inequality below?

5x-9<91
5x<100
x<20

Answer 1

The Multiplication property

Explanation:

The Multiplication property by a constant was used

For real numbers a and b, and c different from zero:

If c is positive and
`a <b` then
`a*(1)/(c) <b*(1)/(c)`.

If c is negative and
`a <b` then
`a*(1)/(c) >b*(1)/(c)`.

In this case we have

`5x<100` Then
`(5)/(5)x<(100)/(5)`

Finally

`x<20`