Because you have to go in the order of PEMDAS, parenthesis, exponents, multiplication, division, addition, and subtraction. From what you are saying, 'why you must simplify 3 to the second power first' it seems that you have no parenthesis, so you move onto what is next, which is exponents, in this case, 3 to the power of two.
Answer: C. 5(6) + 0.65y
Step-by-step explanation:
Process of elimination.
65% of y = 0.65y
A has 65y, completely incorrect.
B has 6y, also completely incorrect.
<u>C has 0.65y, correct.</u>
D has 1.65y, also completely incorrect.
35% of 51 is 17.85. Hope this helped! :)