# Science:Math Exam Resources/Courses/MATH100/December 2016/Question 04 (a)/Hint 1

A line is tangent to the function ${\displaystyle y=f(x)}$ at ${\displaystyle x=a}$, if first the tangency point lies on both the line and the function, and also the slope of the line is the derivative of the function at ${\displaystyle x=a}$. Therefore,
a function is tangent to the given line if it goes through ${\displaystyle (1,6)}$ and has derivative ${\displaystyle 4}$ at that point.