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What is the discriminant of x^2=4?Please show steps on how you got that answer.

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babyryan95 | Honors

Posted July 12, 2012 at 3:32 AM via web

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What is the discriminant of x^2=4?

Please show steps on how you got that answer.

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embizze | High School Teacher | (Level 1) Educator Emeritus

Posted July 12, 2012 at 4:23 AM (Answer #1)

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Given a quadratic equation in standard form `ax^2+bx+c=0` , the discriminant is `b^2-4ac` .

Rewriting `x^2=4` in standard form we get:

`x^2-4=0` where a=1,b=0,c=-4

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The discriminant is `0^2-4(1)(-4)` or 16

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Sources:

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atyourservice | Student, Grade 10 | Valedictorian

Posted February 23, 2014 at 5:49 PM (Answer #2)

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`x^2=4`   to find the discriminant use the formula `b^2-4ac`

the first thing is to take away `4`

`x^2-4=4-4`

`x^2-4=0`

`a=1 `  b would be 0 as there is no b value    `c=-4`     plug in these numbers

`0^2-4(1)(-4)`  simplify it

0+16  set it up as an equation

`0+16=16 `  so the discriminant is 16 and the problem has 2 real solutions

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