 You should already know how to derive expressions and equations from sentences, but if you're unsure, you may want to watch this video first. We can also derive formulae, such as area and volumes, or quadratics. So let's jump straight in. What is the area of the orange square? As it's a square, it must be 4x squared, and the area of the blue circle has a radius of x, and using the area of the circle is pi radius squared, it must be pi x squared. So what's the orange shaded area? Pause the video and finish off the question. Did you get one of these answers? Either one is correct. So how about this question? Pause the video and give them a go. Did you simplify the perimeter fully to 6a plus 8, and the area to 6a plus 12? A typical question you will come across is something like this. We're given a shape in an area and asked to show that. The show that is what we're aiming to get to at the end of our working, but it's really just for us to check our answer is correct. So we actually ignore it for now, and just focus on these pieces of information. So the area equals 36. Do you remember that the area of a trapezium is half the sum of the parallel sides times the distance between them? Use the information in the diagram to write an expression in terms of x to the area of the trapezium, and make it equal to 36. Pause the video and see how you get on. Did you end up with a correct equation? You may come across quite a few of these. Show that. Quadratic questions. So ignore the show that part and only really use it to check your answer is correct. Give this one a go. You're finding the area of the t-shape. Pause the video and work it out. Did you get it right? The area of one rectangle plus the area of the other added together equal 20 cm2. Then expand and simplify and rearrange to get the final answer. So there we have deriving formulae and equations from written sentences or diagrams. Just take them step by step and ignore the show that part except for checking your final answer. If you liked the video, give it a thumbs up and don't forget to subscribe, comment below if you have any questions. Why not check out our few school app as well. Until next time.