Where does the 1 come from in this problem? The one that is under 1-r. We needed to solve for a? I'm just not sure why they put the 1

Idont understand math at all! : o( use this scenario to answer the remaining questions: brenton purchased a new bedroom set for $4,500.00. he lives in arizona and pays a 8.75% sales tax. if he made a 50% down payment and financed the rest, what amount did he finance? what is the total sales tax brenton will pay? enter your answer in currency format, round to the nearest cent. what was brenton's total amount financed? enter your answer in currency format, round to the nearest cent.

The fraction 7/9 is equivalent to a percent that is greater than 100%. truefalse

What is the value of x in this triangle? a. 53° b. 62° c. 65° d. 118°