To find the mean add up all the numbers and divide. The mean absolute deviation is the difference.
X^2 + 5x = -2
x^2 + 5x + 2 = 0
x = -b (+-) sqrt (b^2 - 4ac) / 2a
a = 1, b = 5, and c = 2
x = -5 (+-) sqrt (5^2 - 4(1)(2)) / 2(1)
x = -5 (+-) sqrt (25 - 8) / 2
x = -5 (+-) sqrt (17) / 2
answer is : negative 5 plus or minus the square root of 17 divided by 2
Just substitute it into the gradient formula which is: y2 - y1 / x2 - x1. So 2-3/2-9 = -1/-7 = 1/7