How do you solve using the quadratic formula $x^2-25=0$ ?

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Answer 1 · 2015-05-07T21:01:48

If you really must use the quadratic formula,
we need to express our equation in the form:
$ax^2+bx+c=0$

$x^2-25=0$
becomes
$(1)x^2 +(0)x +(-25) =0$

The quadratic formula tells us the solution(s) is/are
$x=(-b+-sqrt(b^2-4ac))/(2a)$
or, for our example
$x=(0 +-sqrt(0^2-4(1)(-25)))/(2(1))$

$x= +-sqrt(100)/2$

$x=+-10/2$

$x=+-5$

How do you solve using the quadratic formula x^2-25=0x^2-25=0?