Answer: In mathematics, a function is any expression that produces exactly one answer for any given number that you give it. The input is the number you feed into the expression, and the output is what you get after the look-up work or calculations are finished.
Step-by-step explanation:
Y=-x^2 is just y=x^2 reflected over the x-axis. In other words, the parabola is upside-down.
It's been a while since I've done algebra but the answer that I got was x=4
