// Numbas version: exam_results_page_options {"name": "Unit 4 - Which quadratic function is shown by the parabola?", "extensions": ["jsxgraph"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"rulesets": {}, "parts": [{"showFeedbackIcon": true, "maxMarks": 0, "variableReplacementStrategy": "originalfirst", "displayColumns": 0, "type": "1_n_2", "matrix": "[2,0,0,0,0]", "steps": [{"variableReplacements": [], "showFeedbackIcon": true, "scripts": {}, "variableReplacementStrategy": "originalfirst", "marks": 0, "prompt": "

You can narrow down the choices by checking points where the curve intersects the axes, in particular, the $y$-axis intercept. In addition, the $x$-coordinate of the vertex of the parabola is $x=\\frac{-b}{2a}$, when the curve is written in the standard form $y=ax^2+bx+c$. The line $x=\\frac{-b}{2a}$ is also the vertical line of symmetry for the curve.

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Decide which of the following expressions for $f(x)$ corresponds to the parabola shown.

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$\\\\var{a_inverse}\\\\simplify{x^2+{b}}\\\\simplify{x+{c}}$

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$\\\\frac{1}{\\\\var{a_inverse}}\\\\simplify{x^2+{b}}\\\\simplify{x+{c}}$

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$\\\\var{a_inverse}\\\\simplify{x^2+{b}}\\\\simplify{x-{c}}$

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$\\\\frac{1}{\\\\var{a_inverse}}\\\\simplify{x^2+{b}*3}\\\\simplify{x+{c}}$

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$(\\\\simplify{x+{c}})^2+\\\\simplify{x+{b}}$

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The curve $y=f(x)$ is shown below.

\n\n\n\n\n\n\n
{drawgraph()}
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Tests the ability to match a quadratic function to a given parabola.

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