Understanding Quadratic Functions Concepts

This tutorial explains quadratic graphs, focusing on their general form, the shape of parabolas, and key features like the line of symmetry and vertex. It provides guidance on sketching quadratic graphs, including finding intercepts and using the completing the square method.

What is the general form of a quadratic equation?

• y = ax^2 + bx + c

• y = ax^3 + bx^2 + c

• y = ax^2 + b

• y = ax + b

In the quadratic equation y = ax^2 + bx + c, what must be true about 'a'?

• 'a' must be negative

• 'a' must be positive

• 'a' can be zero

• 'a' cannot be zero

What shape does a quadratic graph take when 'a' is positive?

• An inverted U-shape

• A circle

• A U-shape

• A straight line

What is the line of symmetry in a parabola?

• A vertical line through the vertex

• A horizontal line

• A line parallel to the x-axis

• A diagonal line

How can you find where a quadratic graph crosses the y-axis?

• Set x to zero

• Set y to zero

• Find the vertex

• Use the quadratic formula

What method can be used if a quadratic equation does not factorize?

• Quadratic formula

• Completing the square

• Trial and error

• Graphical method

What is the purpose of completing the square in quadratic equations?

• To eliminate the x term

• To find the vertex form

• To find the y-intercept

• To simplify the equation