Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Simultaneous equations. Help please?

I'm confused with this question because there is a y and a y^2.

Could you help please?

y=2x-3

y^2=8x-16

3 Answers

Relevance
  • Anonymous
    1 decade ago
    Favorite Answer

    take the value of y in the first equation, that is 2x-3) and put it into the second equation in place of y. Now the second equation is all in x's and you can solve.

    (2x-3)^2 = 8x - 16

    4x^2 -12x + 9 = 8x - 16

    4x^2 - 20x + 25 = 0

    (2x-5)^2 = 0

    2x-5 = 0

    2x = 5

    x = 5/2

    Now take this x and put it back into the first equation and you can solve for y.

  • 1 decade ago

    (y=2x-3)^2

    y^2=(2x-3)*(2x-3)

    =4x^2-12x+9

    must be equal to 8x-16 from eq. 2

    4x^2-20x+25=0 factors to (2x-5)^2=0

    The two equations are consistent only when x=5/2

  • 1 decade ago

    You need to find the square root of the second one to solve for y.

    y=sqrt(8x-16)

Still have questions? Get your answers by asking now.