Answer:
n = -5, 3.
Step-by-step explanation:
n^2 + 2n - 15 = 0
Let's check if we can factor this quadratic:
We need 2 numbers whose product is -15 and whose sum is +2.
There are 2 such numbers and they are +5 and -3, so the factors are:
(n + 5)(n - 3) = 0.
n + 5 = 0 or n - 3 = 0
therefore the zeroes are -5 and 3.
You should be thinking about a negative number. In fact, you should be thinking about a number that is the opposite of 5! -5! So, the additive inverse of 5 is -5
Mean:
Median: 63, 66, 67, 68, 73, 74, 76, 78, 80, 83, 86, 87, 88, 89, 89, 89, 93, 93, 95, 99, 100
= 169/2
Mode: 100