Answer:
Step-by-step explanation:
The absolute value function is {x, x≥0; -x, x<0} That needs to be multiplied by 3 to get the f(x) in the given problem.
f(x) = 3|x| = 3{x, x≥0; -x, x<0}
f(x) = {3x, x≥0; -3x, x<0} . . . . correct function definition
Compared to the student's answer, the student has reversed the comparison symbols.