## Unit 08 Sets and Functions (General Mathematics 9 PCTB)

Notes, solutions of unit 08, General Mathematics 9, for Punjab Curriculum & Textbook Board (PCTB), Lahore.

* Identify pair of real numbers as an ordered pair.

- Recognize an ordered pair through different examples.
- Describe rectangular or Cartesian plane consisting of two number lines interesting at right angles at the point $O$.
- Identify origin $(O)$ and coordinate axes (horizontal and vertical axes or $x-axis$ and $y-axis$) in the rectangular plane.
- Locate an ordered pair $(a, b)$ as a point in the rectangular plane and recognize.
- $a$ as the $x$-coordinate (or abscissa),
- $b$ as the $y$-coordinate (or ordinate).

- Draw different geometrical shapes (e.g., line segment, triangle and rectangle etc.) by joining a set of given points.
- Construct a table for pairs of values satisfying a linear equation in two variables.
- Plot the pairs of points to obtain the graph of a given expression.
- Choose an appropriate scale to draw a graph.
- Draw a graph of
- an equation of the form $y = c$,
- an equation of the form $x = a$,
- an equation of the form $y = mx$,
- an equation of the form $y = mx + c$.

- Draw a graph from a given table of (discrete) values.
- Solve appropriate real life problems.
- Interpret conversion graph as a linear graph relating to two quantities which are in direct proportion.
- Read a given graph to know one quantity corresponding to another.
- Read the graph for conversions of the form.
- miles and kilometers, acres and hectares,
- degrees Celsius and degrees Fahrenheit,
- Pakistani currency and another currency, etc.

- Solve simultaneous linear equations in two variables using graphical method.

### View Online