
Home > A2C > Chapter 4 > Lesson 4.2.4 > Problem 4-121
4-121.
y-intercept: y = 7 + 2(0)2 + 4(0) − 5
You will need to factor. There is only one x-intercept.
x-intercept: 0 = 7 + 2x2 + 4x − 5
Since there is only one x-intercept, the vertex must be at the x-intercept. To find the equation in graphing form, use the equation y = a(x − h)2 +k.
y-intercept: (0, 2)
x-intercept: (−1, 0)
vertex: (−1, 0)
y = 2(x + 1)2
Start by finding the x- and y-intercepts.
To find the x-coordinate of the vertex, average the x-intercepts.
To find the y-coordinate of the vertex, substitute the x-coordinate of the vertex into the given equation and solve for y.
Now write the equation in graphing form.