C.
A doesn't work because x + x + x = 3x, not x^3.
B doesn't work because 14x + 10 - 2x has like terms, 14x and -2x can be combined, bit when you do so you get 14x - 2x, or 12x + 10. (So not 16x + 10)
D doesn't work because 12x^2 + 5x + 10 doesn't simplify; it can only be factored, and you cannot combine 12x^2 and 5x because their variables have different powers.
C, however, works fine. All they did is factor out a 3; if you distribute that 3 again, you get 12x + 16x back, so the two are equal.
Answer:
20 students.
Step-by-step explanation:
The <u>first </u>person said 5 (which is 5 x 1), the <u>second </u>person said 10 ( which is 5 x2)... we see that this is a arithmetic sequence where the first term is 5 and the nth term is 100. We know that 100 = 5 x 20, therefore, the number of students that counted all the way up to 100 was 20 and Bobby was wrong.
40÷5= 8 You have to see how many time 5 can go into 40
1. see how many times 5 goes into 4 none so the first number is 0
2. then you see how many time 5 can go into 0 o times
3. so you have to see how many time you can count 5 into 40
(count by 5's) 5,10,15,20,25,30,35,40 that should be 8 times total!