The property used is B: addition property
Step-by-step explanation:
The addition property of equality states that if you add the same number to both sides of an equation, the equation balances.In this case;
5x-9<91------------performing addition property of equality
5x-9+9<91+9
5x<100----------performing division property
5x/5<100/5
x<20 ------answer
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Addition Property : https://brainly.com/question/3474035
Keyword : property, inequality
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