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A quadratic equation (equivalent to $(x+a)^2-b$) is given and sketched. Three equations are given that can be solved using the graph. There is a chance there will only be one solution.
"}, "statement": "", "advice": "See 4.1 for background on quadratics. See 1.1 for what solving means.
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\nBelow is a graph. Note that it is symmetrical.
\n\n(i) When the $x$-coordinate on the graph is $\\var{x[1]}$, what is the $y$-coordinate? [[0]]
\n\n(ii) When the $x$-coordinate on the graph is $\\var{x[4]}$, what is the $y$-coordinate? [[1]]
\n\n(iii) When the $y$-coordinate on the graph is $\\var{y[0]}$, what is the $x$-coordinate? [[2]]
\n\n(iv) When $y=0$, there are two possible $x$-coordinates. One of them is $\\var{x'}$. By using the symmetry of the graph, determine the other possibility. Give your answer to 2 decimal places. [[3]]
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