If x-7 =0
Then x =7
Substitute x=7 into f(x):
2(7)^2 - 11(7) + k
= (98-77)+k
= 21+k
Therefore k=-21 because 21+(-21)=0
Answer: The answer is 11x+11y
Attached is a screenshot of spreadsheet used to do this problem.
You will see the excel functions used for each column. The average score is highlighted in blue.
Answer is -9
Multiplying by 1/4 is the same as dividing by 4
-36(1/4) = -36/4 = -9