Electromagnetic (EM) waves
Four thousand one hundred eighty
First set change the function f(x) to y so
that it would be

Then set y = 0

Then solve for x
X = - 3
To graph it, just plot the point (-3,0) on the x-axis
Im not too sure, but C might work as an answer...
Sorry if it's wrong :(
The third one is the correct choice because the solutions are 2 and -2