The summation symbol means we use the variable i in the equation from the given range. In this case, we are given with the equation 3 i - 15 and i ranges from 2 to 7. The summation using simply the calculator is equal to -9. The answer to this problem is -9.
Evaluate the function at the three values of the range and see what you get. The appropriate choice is ...
... D) {15, 3, 0}
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Evaluation can sometimes be simpler if you rearrange the function to a form called "Horner's form."
... f(x) = (x -4)x +3
Then the evaluation looks like (for x=-2) ...
... f(-2) = (-2-4)(-2)+3 = (-6)(-2) +3 = 12 +3 = 15
This is sufficient to identify D as the answer of choice.
Answer:
x=13
Step-by-step explanation:
2.6+10.4=13