Answer:
c. 14
Step-by-step explanation:
Let the missing y value be y2.
If the data represent a linear function, then:



Multiply both sides by 2


Add 6 to both sides


The missing value is 14
The first one is a reflection over the x-axis :)
(6 + 5x)(7x + 3) = 42x + 18 + 35x^2 + 15x = 35x^2 + 57x + 18
We know that the slope formula is m = (y1 - y2)/(x1 - x2)
Your points are: (3, 7) and (4, -8)
In this case,
x1 = 3
x2 = 4
y1 = 7
y2 = -8
Now, just plug in the numbers:
m = (7 - -8)/(3-4)
m = 15/-1
m = -15
Your slope is -15.