Functions

What this exam is like

The Functions exam has 25 multiple-choice questions across these levels: Secondary (25). Each attempt draws 10 at random from the level you choose. You get two tries per question, and each answer is explained afterwards. At the end you see your grade.

Sample questions

1. 1. What does "m" represent in the linear function y = mx + b?

   • The domain
   • The slope
   • The x-axis
   • The y-intercept
   Show the answer

   ✅ The slope

   In y = mx + b, "m" is the slope: it shows how much the line rises or falls per unit along x. If m > 0 the line goes up, if m < 0 it goes down, if m = 0 it is horizontal.

2. 2. If y = −x + 4, what is y when x = 6?

   • −10
   • −2
   • 10
   • 2
   Show the answer

   ✅ −2

   Substitute x = 6: y = −(6) + 4 = −6 + 4 = −2. Watch the negative sign: −x means multiply x by −1.

3. 3. What is the range (or image) of a function?

   • The length of the graph
   • The set of all values y can take
   • The set of values x can take
   • Where it crosses the X axis
   Show the answer

   ✅ The set of all values y can take

   The domain is the inputs and the range the outputs. In y = x² the domain is every number, but the range is only values greater than or equal to 0, because a square is never negative.