Why is there a question mark?
This is probably wrong but my guess is 13 so maybe verify it but that’s my best!
Answer:
9
Step-by-step explanation:
15(8-2)
15-(6)
9
Answer:2.50cm
Step-by-step explanation:
Answer:

» Collect like terms, r terms on the left hand side by subtracting r from both sides and adding st to both sides

» On the left hand side, factorise out r
