Subject-Appears-Twice Edexcel Higher

Subject appears twice

How do I rearrange formulae where the subject appears twice?

• If the subject appears twice, you will need to factorise at some point

  • E.g. When making the subject of

  • Factorise out on the left to get

    • Notice that the subject now only appears once!

  • Then divide both sides by <img alt=”open parentheses 1 plus y close parentheses” data-mathml=”<math ><semantics><mfenced><mrow><mn>1</mn><mo>+</mo><mi>y</mi></mrow></mfenced><annotation encoding=”application/vnd.wiris.mtweb-params+json”>{“fontFamily”:”Times New Roman”,”fontSize”:”18″,”autoformat”:true,”toolbar”:”<toolbar ref=’general’><tab ref=’general’><removeItem ref=’setColor’/><removeItem ref=’bold’/><removeItem ref=’italic’/><removeItem ref=’autoItalic’/><removeItem ref=’setUnicode’/><removeItem ref=’mtext’ /><removeItem ref=’rtl’/><removeItem ref=’forceLigature’/><removeItem ref=’setFontFamily’ /><removeItem ref=’setFontSize’/></tab></toolbar>”}</annotation></semantics></math>” height=”22″ role=”math” 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