Practice With Standard, Vertex, and Factored Form

Answer explanation

Since the vertex is given, write in the vertex form.

Answer explanation

(1, 0) and (7,0) are x-intercepts so write in the factored form.

Answer explanation

Since you know the y-intercept and concavity, write in the standard form.

Answer explanation

Recall roots are the same thing as the x-intercepts, so write in the factored form.

• Standard Form

• Factored Form

• Vertex Form

Answer explanation

The maximum or minimum point of a parabola is its vertex, so write in the vertex form.

Find the vertex form and the intercept form of the quadratic:
y = x² + 4x + 3

• y = (x-2)² -15
  y = (x+1)(x-3)

• y = (x+2)² + 15
  y = (x-1)(x+3)

• y = (x-2)² + 15
  y = (x+1)(x+3)

• y = (x+2)² + 15
  y = (x-1)(x-3)

Find the equation of a parabola with vertex (0, -3) that passes through point (4, -1).

• y = ¹/₈x² - 3

• y = ¹/₈x² -1

• y = ¹/₈x² + 3

• y = ¹/₈x² - 2

What is its equation?

• f(x) = -9x² + 18x +40

• f(x) = 9x² + 18x - 40

• f(x) = 9x² - 18x +40

• f(x) = -9x2 -18x + 40

Practice Problem 4

use y instead of f(x)

Mathematical Equivalence

ON

The graph shows a parabola and it's focus. Write the equation in vertex form.