SOLUTION: how do i solve -x^2-4=18 by graphing, factoring,square roots,completing the square, and the quadratic formula

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: how do i solve -x^2-4=18 by graphing, factoring,square roots,completing the square, and the quadratic formula      Log On


   



Question 174812: how do i solve -x^2-4=18 by graphing, factoring,square roots,completing the square, and the quadratic formula
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
-x%5E2+-+4x+=+18 Is this it? Did you just forget the x?
Subtract 18 from both sides
-x%5E2+-+4+-+18+=+0
Now write it as the function
y+=+-x%5E2+-+4x+-+18
Now find where y=0 on the graph
+graph%28+500%2C+500%2C+-10%2C+10%2C+-70%2C+5%2C-x%5E2+%2B+4x+-+18+%29+
Notice the curve does not intersect the x-axis
That means the roots are imaginary.
This is as far as I'm going, since I'm
not really sure what you were trying
to write