Question

Create two different explicit equations that describe the values in the table. Use a different point in the table for each of the equations you create. Choose one of the equations you created to produce an equivalent form that reveals the y intercept of the function within the equation.

Answer 1

Explanation:

if x were starting at 0, we would have

y = (x - 7)×7 = 7x - 49

but we start at x = 57. We need adjust for these extra 57 to get the above equation.

so, it

y = (x - 57 - 7)×7 = (x - 64)×7 = 7x - 448

so, for

y = (x - 64)×7

I choose x = 57

y = (57 - 64)×6 = -7×7 = -49

for

y = 7x - 448

I choose x = 58

y = 7×58 - 448 = 406 - 448 = -42

from this form we get the y-intercept (the y- value when x = 0) : -448