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Math Help - Finding x & y intercepts (found the y-intercept)

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    Finding x & y intercepts (found the y-intercept)

    I need help please with finding the x-intercept for the following:

    y = -2x^2 +4

    I got the y-intercept (0,4) by setting x = 0

    However, when I set y = 0 and attempt to solve I get stuck

    0 = -2x^2 + 4

    What are the next steps for finding the x-intercept? Thanks in advance!
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    x= \pm \sqrt 2?
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    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by lilrhino View Post
    I need help please with finding the x-intercept for the following:

    y = -2x^2 +4

    I got the y-intercept (0,4) by setting x = 0

    However, when I set y = 0 and attempt to solve I get stuck

    0 = -2x^2 + 4

    What are the next steps for finding the x-intercept? Thanks in advance!
    0 = -2x^2 + 4 .........subtract 4 from both sides

    \Rightarrow -4 = -2x^2 .........Now divide through by -2

    \Rightarrow 2 = x^2 .............Now take the squareroot of both sides

    \Rightarrow \pm \sqrt {2} = x

    So our x-intercepts are: \left( \sqrt {2} , 0 \right) \mbox { and } \left( - \sqrt {2} , 0 \right)
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