A quadratic function is given. The graph of the function is drawn with three coordinates on the graph, without any x or y ticks. The $x$ coordinate is given for a couple and $y$ coordinate given for the third, and coordinates are asked for.
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", "advice": "See ??
\nFor the $x$-coordinate of $C$, the calculations should give you two choices. Look at the diagram to make the appropriate choice.
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\n{plot(a,b,0,x[0], fx[0], x[1], fx[1], x[2], fx[2])}
\nThe $x$-coordinates of $A$ and $B$ are $\\var{x[0]}$ and $\\var{x[1]}$, respectively.
\nThe $y$-coordinate of $C$ is $\\var{fx[2]}$.
\nDetermine the coordinates of $A,B$ and $C$.
\n\nCoordinates of A: [[0]]
\nOf B: [[1]]
\nOf C: [[2]]
\n", "gaps": [{"type": "matrix", "useCustomName": false, "customName": "", "marks": 1, "showCorrectAnswer": true, "showFeedbackIcon": true, "scripts": {}, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "adaptiveMarkingPenalty": 0, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "correctAnswer": "matrix([x[0],fx[0]])", "correctAnswerFractions": false, "numRows": 1, "numColumns": "2", "allowResize": false, "tolerance": 0, "markPerCell": false, "allowFractions": false}, {"type": "matrix", "useCustomName": false, "customName": "", "marks": 1, "showCorrectAnswer": true, "showFeedbackIcon": true, "scripts": {}, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "adaptiveMarkingPenalty": 0, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "correctAnswer": "matrix([x[1],fx[1]])", "correctAnswerFractions": false, "numRows": 1, "numColumns": "2", "allowResize": false, "tolerance": 0, "markPerCell": false, "allowFractions": false}, {"type": "matrix", "useCustomName": false, "customName": "", "marks": "2", "showCorrectAnswer": true, "showFeedbackIcon": true, "scripts": {}, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "adaptiveMarkingPenalty": 0, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "correctAnswer": "matrix([x[2],fx[2]])", "correctAnswerFractions": false, "numRows": 1, "numColumns": "2", "allowResize": false, "tolerance": 0, "markPerCell": false, "allowFractions": false}], "sortAnswers": false}], "type": "question", "contributors": [{"name": "Lovkush Agarwal", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1358/"}]}]}], "contributors": [{"name": "Lovkush Agarwal", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1358/"}]}