On week 12 of math 10 we’ve learned how to find coordinates using function notation. In function notation f(x) is our output and x our input. We have a picture of a graph.
What if we have to find f(3).
f(3)=? 3 here represents x so we need to find 3 on x-axis. After we found 3 we have to look for y coordinate that passes our point. if we will draw a line we will see that our y coordinate is -1. f(3)=-1
What if f(7), then we are looking for 7 on x-axis and drawing a line with our eyes to find y coordinate that passes 7. This y coordinate is 3. f(7)=3
What if we have to find f(x)=3 this means now we have to find 3 on y-axis. And then draw imaginary horizontal line to find x. By imagining the line we find that x=-3, so f(-3)=3