A variable is a letter that represents a number. Don't let the fact that it is a letter throw you. Since it represents a number, you treat it just like you do a number when you do various mathematical operations involving variables. Evaluating an Expression You evaluate an expression by replacing the variable with the given number and performing the indicated operation.
To this end, two lines are drawn at a right angle. The horizontal one is called the x axis and the vertical one is called the y axis. Where the x axis and the y axis intersect is the "0" zero point see Fig.
The plotting of the information on the graph is discussed in the following examples. Each week the height of the plant is measured. One week after planting the seed, the plant measures 2 cm in height, two weeks after planting it measures 5 cm and 3 weeks after planting the height is 10 cm, as illustrated in Fig.
Measuring the growth rate of a maize plant These results can be plotted on a graph. The time in weeks will be indicated on the x axis; 2 cm on the axis represents 1 week.
The plant height in centimetres will be indicated on the y axis; 1 cm on the axis represents 1 cm of plant height. After 1 week the height is 2 cm; this is indicated on the graph with A; after 2 weeks the height is 5 cm, see B, and after 3 weeks the height is 10 cm, see C, as shown in Fig.
Now connect the crosses see Fig. The line indicates the growth rate of the plant; this is the height increase over time.
Growth rate of a maize plant It can be seen from the graph that the plant is growing faster and faster during the first week 2 cm and during the third week 5 cm ; the line from B to C is steeper than the line from D to A.
From this crossing follow the dotted line to the left until the vertical axis is reached. Now take the reading: This height has not been measured in reality, but with the graph the height can be determined anyway. Graph of the growth rate of a maize plant 1. Suppose the outside temperature always in the shade is measured, with a thermometer, every two hours, starting at midnight and ending the following midnight.
Suppose the following results are found:Guide the student to interpret the expression 8x + 4 in terms of x, the width of the rectangle. Provide a value of x, and have the student use the expression 8x + 4 to calculate the perimeter of the rectangle. Ask the student to describe what the expression indicates about using the width to calculate the perimeter.
Have the student compare . Set the drawing transformation matrix for combined rotating and scaling. This option sets a transformation matrix, for use by subsequent -draw or -transform options..
The matrix entries are entered as comma-separated numeric values either in quotes or without spaces. Before we can find the dimensions of the rectangle, we need find w first. Here's how: 1) Write an equation that relates 45cm 2, w+4 and w.
To do so, we know that the area of the rectangle, 45cm 2 can be found by multiplying w with w+urbanagricultureinitiative.com, we have.
Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for.
several web pages intended for students; this seems to be the most popular one. FONTS FINALLY REPAIRED November Browser adjustments: This web page uses sub scripts, super scripts, and unicode urbanagricultureinitiative.com latter may display incorrectly on your computer if you are using an old browser and/or an old operating system.
1 The Organization of the Screen. On a graphical display, such as on GNU/Linux using the X Window System, Emacs occupies a graphical window. On a text terminal, Emacs occupies the .