Answer: With a variable. A variable is a letter you use in an equation , like this: 7+x=14, X is a classic one but you can use any letter u please! (In my school at least.)
To answer this you could do a couple things. 1. Actually calculate both tips and then subtract them. Here is the math ( assuming it is $60, not 60% that you mean). a. 0.15 x 60 = $9. b. 0.0825 x 2 x 60=$9.90. c. 9.90-9.00= $0.90 difference.
The other strategy would be to find the difference on the percents and then multiply by $60. a. 8.25%x2=16.5%-15%. Difference of 1.5%. b. 0.015 x $60=$0.90.
The second option is the correct answer

The expression given to us is:

Herein, we can simplify it by opening up the bracket and multiplying each term inside the bracket by the term which is outside the bracket.
Thus, we get:


Rearranging the above expression in descending order of power we get:

From the given options we can see this is the second option. Hence the second option is the correct answer.
Learn more about equation here brainly.com/question/14180340
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