Part A: Yes, the data represent a function. The definition of a function is a relation in which no value of x will have two different values of y.
(Every time you plug in 3 as x, you will always get 4 as y; it's ok if you plug in 3 and 5 as x and get the same y, you just can't get two different y's for one x; sorry, it is pretty confusing). None of the numbers in the table repeat, so we can safely say that the relation is a function.
Part B: All we have to do is plug in 11 for x in the function given to find the answer:
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In the table, y = 8 when x = 11, but in the function given, y = 34 when x = 11, so the function given is greater.
Part C: To find the answer to C, just plug in 99 for f(x), as it tells you to do:
2X^2+4X-8-X^2+6X-4
X^2+4X-8+6X-4
X^2+10X-12
12×4=48 , 68×12 is a much greater number.
Plus a negative value becomes subtraction:
-12 + -23 = -12 -23 = -35
Answer:
The answer is 12
Step-by-step explanation:
Step 1: $26.95 - $8.95 (which equals $18.00)
Step 2: 18 divided by 1.50 (which equals 12)