Q. the graph of (y = 5x^2) is the graph of (y = x^2).
Answer
The graph of \( y = 5x^2 \) is the graph of \( y = x^2 \) vertically stretched by a factor of 5 (each y-value is multiplied by 5); the vertex stays at \( (0,0) \) and the parabola opens upward.
Detailed Explanation
Problem
Compare the graph of \(y = 5x^2\) with the graph of \(y = x^2\). Explain step by step what the relationship is and how to produce the graph of \(y = 5x^2\) from the graph of \(y = x^2\).
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Write each function clearly.
Base parabola: \(y = x^2\).
Transformed parabola: \(y = 5x^2\), which can be written as \(y = 5\,(x^2) = 5\cdot f(x)\) where \(f(x)=x^2\).
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Interpret the algebraic change.
Multiplying \(f(x)\) by 5 means every output (every y-value) of the base graph is multiplied by 5. For each x, the new y is
\(y_{\text{new}} = 5\cdot y_{\text{old}}\).
So the mapping of points is \((x, y_{\text{old}})\) becomes \((x, 5\,y_{\text{old}})\).
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Describe the geometric transformation.
This multiplication of y-values is a vertical stretch by a factor of 5 (a vertical dilation with scale factor 5) about the x-axis. Distances from the x-axis are multiplied by 5; x-coordinates do not change.
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Compare key features.
- Vertex: both parabolas have the same vertex at \((0,0)\) because \(5\cdot 0^2 = 0\).
- Axis of symmetry: both have the y-axis as axis of symmetry (the line \(x=0\)).
- Direction and concavity: both open upward (concave up) because the coefficient of \(x^2\) is positive in both cases.
- Steepness/narrowness: \(y = 5x^2\) is steeper (narrower) than \(y = x^2\) because y-values grow 5 times faster for the same x.
- Intercepts: solving \(5x^2=0\) gives \(x=0\), so the only x-intercept and the y-intercept are both at the origin \((0,0)\).
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Compare specific points (numerical check).
Take sample x-values and compute both y-values:
For \(x=-2\): \(y_{base}=(-2)^2=4\). For transformed: \(y_{new}=5\cdot 4=20\). Point moves from \((-2,4)\) to \((-2,20)\).
For \(x=-1\): \(y_{base}=1\). New: \(y_{new}=5\). Point moves from \((-1,1)\) to \((-1,5)\).
For \(x=0\): \(y_{base}=0\). New: \(y_{new}=0\). Point stays \((0,0)\).
For \(x=1\): \(y_{base}=1\). New: \(y_{new}=5\). Point moves from \((1,1)\) to \((1,5)\).
For \(x=2\): \(y_{base}=4\). New: \(y_{new}=20\). Point moves from \((2,4)\) to \((2,20)\).
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How to draw \(y = 5x^2\) from \(y = x^2\) — step-by-step instructions.
- Plot several points of the base graph \(y = x^2\), for example \((-2,4)\), \((-1,1)\), \((0,0)\), \((1,1)\), \((2,4)\).
- Multiply each y-coordinate by 5 to get the new points: \((-2,20)\), \((-1,5)\), \((0,0)\), \((1,5)\), \((2,20)\).
- Plot these new points on the same axes.
- Draw a smooth parabola through the new points; it will be narrower and steeper than \(y = x^2\) but share the same vertex and axis.
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Conclusion (concise answer).
The graph of \(y = 5x^2\) is not the same as the graph of \(y = x^2\). It is the graph of \(y = x^2\) vertically stretched by a factor of 5 about the x-axis. Every y-value of \(y = x^2\) is multiplied by 5 to obtain \(y = 5x^2\).
Graph
FAQs
Is the graph of \(y=5x^2\) the same as the graph of \(y=x^2\)?
What does “vertical stretch by factor 5” mean for \(y=5x^2\)?
How do key features compare: vertex, axis, domain, and range?
How do specific points change? For example, compare \(x=1\) and \(x=2\).
How does the slope (steepness) compare?
How can I graph \(y=5x^2\) using transformations?
How does the focus and directrix change?
Can I write \(y=5x^2\) as a transformation of a function notation?
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