Question

1. At what point does the graph of f(x)=3x-12 crosses the x-axis?

2.At what point does the graph of f(x)=5x+1 crosses the y-axis?

Answer 1

The function is zero when it crosses the x axis so

0 = 3 x - 12
12 = 3 x
x = 4
----------------------------
When it crosses the y axis x = 0 so
f(0) = 5(0) + 1
f(0) = 1