Example

Graphing y=25x2+10x+1y = 25x^2 + 10x + 1

To graph the parabola y=25x2+10x+1y = 25x^2 + 10x + 1, apply the standard graphing procedure:

Step 1: The coefficient a=25a = 25 is positive, so the parabola opens upward.

Step 2: Find the axis of symmetry using x=b2ax = -\frac{b}{2a}. Since b=10b = 10 and a=25a = 25, x=102(25)=1050=15x = -\frac{10}{2(25)} = -\frac{10}{50} = -\frac{1}{5}. The axis of symmetry is the line x=15x = -\frac{1}{5}.

Step 3: Find the vertex by substituting x=15x = -\frac{1}{5} into the equation: y=25(15)2+10(15)+1=25(125)2+1=12+1=0y = 25(-\frac{1}{5})^2 + 10(-\frac{1}{5}) + 1 = 25(\frac{1}{25}) - 2 + 1 = 1 - 2 + 1 = 0. The vertex is the point (15,0)(-\frac{1}{5}, 0).

Step 4: Find the yy-intercept by setting x=0x = 0: y=25(0)2+10(0)+1=1y = 25(0)^2 + 10(0) + 1 = 1. The yy-intercept is (0,1)(0, 1). The point symmetric to the yy-intercept across the axis of symmetry x=15x = -\frac{1}{5} is (25,1)(-\frac{2}{5}, 1).

Step 5: Find the xx-intercepts by setting y=0y = 0: 0=25x2+10x+10 = 25x^2 + 10x + 1. This factors as a perfect square trinomial: 0=(5x+1)20 = (5x + 1)^2. Solving yields 5x+1=05x + 1 = 0, so x=15x = -\frac{1}{5}. The only xx-intercept is (15,0)(-\frac{1}{5}, 0), which coincides with the vertex.

Step 6: Graph the parabola by plotting the vertex, the yy-intercept, and the symmetric point, then connect them with a smooth, upward-opening curve.

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Updated 2026-04-21

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