solve the equation?

Question

x^2 + 16x + 63 = 0

Answer 1

"Your equation is wrong. To solve it mathematically, it should be - 16 x instead of +16 x. In that case, x = -9,-7"

No it isn't.
You can still factorise it.

x^2 + 16x + 63 = 0
(x +7)(x+9)=0
x= -7,-9

Answer 2

Two ways of doing it...

First method:
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You can factorise your equation and write it as
(x+9)(x+7) = 0

That means at least one of the brackets must be equal to zero in order to give a zero on the right hand side. I.e,

x + 9 = 0 or x + 7 = 0

This means
x = -9 or x = -7

Second method:
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You apply the quadratic formula to obtain the solution. It's difficult to type out here, but it's the one involving a "Delta" in it.

x = [ -b (+ or -) sqrt(b^2 - 4ac) ] / 2a

In the equation you gave, a = 1, b = 16 and c = 63. Substitute these into the above formula and you'll get x = -9 and x = -7 as the two solutions.

Answer 3

Your equation is wrong. To solve it mathematically, it should be - 16 x instead of +16 x. In that case, x = -9,-7

Answer 4

i absolutely agree with Mercutio's answer.