// Numbas version: finer_feedback_settings
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Solving x^2-c^2=0", "tags": [], "metadata": {"description": "<p>quadratic solving using difference of two squares</p>", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "<p>Solve the following equation for $x$.</p>\n<p>\\[\\simplify{x^2+{b}x+{c}}=0\\]</p>", "advice": "<p>For a quadratic expression of this form we can make use of the Difference of Squares formula, which states that \\[a^2-b^2 = (a+b)(a-b).\\]</p>\n<p>Therefore,&nbsp;</p>\n<p>\\[\\simplify[unitFactor]{x^2-{c} = (x+{x1})(x-{x1})}.\\]</p>\n<p><a href=\"https://www.sheffield.ac.uk/mash/maths-resources/first-steps#Quadratics\">Use this link to find resources to help you revise how to factorise a quadratic equation using the difference of two squares formula.</a><a href=\"https://www.sheffield.ac.uk/mash/maths-resources/first-steps#Quadratics\" target=\"_blank\" rel=\"noopener\"></a></p>", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, 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