Review question

# Can we show this quartic equation has exactly two real roots? Add to your resource collection Remove from your resource collection Add notes to this resource View your notes for this resource

Ref: R7549

## Suggestion

Sketch in the same diagram the graphs of $y = x^2$ and $x^2 + y^2 - 4x + 2y - 4 = 0$.

What kind of a curve does the first equation give?

How about the second? Can we complete the square here to make the equation clearer?