Question

11.Write the equations of linear and exponential functions that pass through the points (0,9) and (1,3)

Answer 1

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Answer:

  y = -6x +9

  y = 9·(1/3)^x

Step-by-step explanation:

In each case, the y-intercept is 9.

Linear

The slope is rise/run = (3-9)/(1-0) = -6, so the equation is ...

  y = mx + b . . . . . . . slope m, intercept b

  y = -6x +9

Exponential

The ratio of value at x=1 to that at x=0 is 3/9 = 1/3. That is the "growth factor," so the equation is ...

  y = 9·(1/3)^x