Calculations with Square Roots

Calculations with Square Roots gets you ready for Pythagoras' theorem in NSW Year 8 maths (NESA outcome MA4‑IND‑C‑01). A root sign works like a bracket, so in \(\sqrt{5^2 + 12^2}\) you square, add and only then take the root, which gives \(13\) and not \(5 + 12\).

You will evaluate roots of large numbers and decimals such as \(\sqrt{2.25}\), find cube roots, round answers to one decimal place and decide whether a root is exact or a surd. You will also trap a root between two whole numbers and find a missing number under a root sign. A square root gives the side of a square photo from its area. It is part of Year 8 Pythagoras.