What is the value of 3k - 4 when k = 5?

The value of 3k - 4 when k = 5 is 11.

To find the value of the expression 3k - 4 when k is given as 5, we need to substitute the value of k into the expression. This means wherever we see 'k' in the expression, we replace it with 5. So, the expression 3k - 4 becomes 3(5) - 4.

Next, we perform the multiplication first, as per the order of operations (BIDMAS/BODMAS: Brackets, Indices, Division and Multiplication, Addition and Subtraction). Multiplying 3 by 5 gives us 15. Now, the expression is simplified to 15 - 4.

Finally, we perform the subtraction. Subtracting 4 from 15 gives us 11. Therefore, the value of the expression 3k - 4 when k = 5 is 11.

This process of substituting a given value into an algebraic expression and simplifying it step-by-step is a fundamental skill in GCSE Maths. It helps in understanding how variables work and how to manipulate algebraic expressions. Remember to always follow the order of operations to ensure you get the correct result.