Functions: Practice 19

In this Grade 8 lesson on Functions, you will practice solving problems like: "If f(x) = 2x + 1, what is f(2)?". Work through each problem carefully, use the hints if you need help, and check your answers. This builds your understanding of functions step by step.

Watch how

If f(x) = 2x + 1, what is f(2)?

1Read the problem carefully: "If f(x) = 2x + 1, what is f(2)?"

Problem 1 of 5

1

Problem 1

If f(x) = 2x + 1, what is f(2)?

Problem 2 of 5

2

Problem 2

If f(x) = 4x + 3, and f(x) = 19, what is x?

Problem 3 of 5

3

Problem 3

If f(x) = 2x + 5, and f(x) = 11, what is x?

Problem 4 of 5

4

Problem 4

If f(x) = 5x + 6, what is f(7)?

Problem 5 of 5

5

Problem 5

If f(x) = 1x + 6, what is f(1)?

Nice work!

You got 0 of 5 right.

Next: Functions: Practice 20 All lessons

🎯

Next Smart Lesson

We'll pick a lesson that matches exactly where your math is right now.

✨ More to explore

🌍 Where you'd use this: Anytime someone says 'figure out X if you know Y' — you're doing algebra.

🤯 Fun fact: 🤯 The letter 'x' is used for 'unknown' because of an Arabic word that French printers couldn't easily print.

🏆 Try this week: Find one real-life situation today that uses an unknown. Write the equation for it.

👨‍👩‍👧 At dinner: “If x equals your age, what's 2x + 5? What does that number mean?”

𝑓Share card

Challenge a friend

Send it to a parent looking for a 5-minute math win that doesn't feel like homework.

Functions: Practice 19

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Next Smart Lesson

Challenge a friend

Functions: Practice 19

Done with math? Try something else

Your Cart (0)