Plug in the first x value into equation to solve for y. So (-8+2) is 6 and 6 squared is 36 so first coordinate point is (-8,36) just do that for each x value.
Your method is completely correct. The first term will be 6 and each subsequent term can be obtained by adding 6 to the previous one, meaning the common difference is 6. The number of terms is given by the highest number that is divisible by 6 and dividing it by 6; that is 996/6 = 166
Then we simply apply the formula for arithmetic sequence sum:
S = n/2 [2a₁ + (n - 1)d]
S = 166/2 [ 2(6) + (166 - 1)6]
S = 83,166
Your brother would be nine years old.
