Ask questions and get helpful answers.

Use the equation of the exponential function whose graph passes through the points (0,-2) and (2,-50) to find the value of y when x = -2.

I know the formula is y=ab^x but I don't know what numbers to plug in.

Any help would be great.

Thanks.

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩

1 answer

  1. first sub in (0,-2) to get
    -2 = ab^0, but b^0 = 1
    so a=-2
    so far we have

    y = -2b^x

    now use the other point (2,-50)
    -50 = -2(b^2)
    b^2 = 25
    b= ±5
    however in exponentional equations the base is usually positve, so now you have

    y = -2(5^x)

    sub in x=-2 and you got it.

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Answer this Question

Related Questions

Still need help?

You can ask a new question or browse existing questions.