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anonymous

  • one year ago

Using the completing-the-square method, rewrite f(x) = x2 + 4x − 1 in vertex form. f(x) = (x + 2)2 + 1 f(x) = (x + 2)2 f(x) = (x + 2)2 + 4 f(x) = (x + 2)2 − 5

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  1. anonymous
    • one year ago
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    welcome to open study

  2. anonymous
    • one year ago
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    tanks

  3. anonymous
    • one year ago
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    yeah

  4. anonymous
    • one year ago
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    can you help me with this problem

  5. anonymous
    • one year ago
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    what does it mean by "rewrite f(x) = x2 + 4x − 1 in vertex form."

  6. anonymous
    • one year ago
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    @Mehek14

  7. anonymous
    • one year ago
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    @marigirl @moazzam07

  8. marigirl
    • one year ago
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    factorizing, so basically when you expand it out again, you should have your original equation.

  9. anonymous
    • one year ago
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    but how do i turn fx to vetex form

  10. anonymous
    • one year ago
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    vertex

  11. anonymous
    • one year ago
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    o i didnt see where you said factor sorry

  12. marigirl
    • one year ago
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    vertex form also means turning point on graph. i.e at which point on the x axis will the parabola have its minimum point. Best way to go about is start factorizing the equation given to you f(x) = x^2 + 4x − 1 May start factorising first part - x^2+4x .. what will that get us to

  13. anonymous
    • one year ago
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    x(x+4) ???

  14. marigirl
    • one year ago
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    let try it another way .. i am going to factorise it to \[f(x)= (x+2)^{2}\] This will ensure I have it in vertex form... now i need to manipulate it a little so that my final equation will look like \[f(x)=x ^{2}+4x-1\] so now, what constant value will i need to add to the top equation to make it same as the second equation ..

  15. anonymous
    • one year ago
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    i dont know 2?

  16. marigirl
    • one year ago
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    see what u get when you expand f(x)=(x+2^2: we get x^2+4x+4 ..... but i need x^2+4x-1 .. so what number do i need to add/minus so i wil get to x^2+4x-

  17. anonymous
    • one year ago
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    1

  18. marigirl
    • one year ago
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    i need to minus 5

  19. anonymous
    • one year ago
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    where u get that from lol im so confused

  20. marigirl
    • one year ago
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    (x+2)^2-5

  21. marigirl
    • one year ago
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    sorry i dont think i helped...

  22. anonymous
    • one year ago
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    oooo ok i understand wher i am i was confused with the vertex form i mixed it with a different formula

  23. anonymous
    • one year ago
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    no actually you did i just thought to hard

  24. marigirl
    • one year ago
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    ok, well you can always expand the answers given to you and see which is the original equation

  25. anonymous
    • one year ago
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    ok thanksss

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