Page 46 - Math Course 3 (Book 1)

Quadratic Equations

What are the domain and range of the function
x y 2
y = –x + 4?
–2 0
A. D: {x | x is a real number.}R: {y | y < 4}
–1 3 B. D: {x | x is a real number.}R: {y | –2 < y < 2}

0 4 C. D: {x | –2 < x < 2}R: {y | y is a real number.}
D. D: {x | x < 4}R: {y | y is a real number.}
1 3
Answer 2 0 Answer

MO. 2 - L1b

Quadratic Functions: Axis of symmetry

Axis of Symmetry The line that divides a parabola into two halves is
called the axis of symmetry.

Vocabulary A-Z Axis of symmetry
Let us learn some vocabulary The vertical line through the vertex
on the graph of a quadratic equation

vertex Axis of

The maximum or minimum point of a parabola is symmetry
called the vertex.

Key Concept

Maximum
Axis of Symmetry of
a Parabola

Words The equation of the axis of symmetry
Minimum
2
for the graph of y = ax + bx + c,
where a ≠ 0, is x = – b
2a
minimum

The lowest point of the parabola is called Model y
minimum (vertex).

maximum 0 x

The highest point of the parabola is called x = – b
maximum (vertex). 2a

symmetry

Parabolas possess a x =3
geometric property called
symmetry. Symmetrical
figures are those in which
each half of the figure
matches the other exactly.

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