Linear functions and graphing: from tables to real-world applications

Notes

11 Graphs 3 For the function $y = x + 8$: a Copy and complete this table of values. | x | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 | | --- | --- | --- | --- | --- | --- | --- | --- | --- | | y | 5 | | | | | 10 | | | b Draw a graph of the line. c The points $(20, \square)$ and $(-20, \square)$ are on the line. Work out the missing numbers. 4 a Copy and complete this table of values for the function $y = 2x$. | x | -3 | -2 | -1 | 0 | 1 | 2 | 3 | | --- | --- | --- | --- | --- | --- | --- | --- | | y | | | | | | | | b Use the table to draw the line $y = 2x$. c Here are some points on the line. Copy and complete the coordinates. i (4.5, □) ii (-5, □) iii (8.5, □) iv (-8, □) d (1, 3) is above the line and $(-2, -6)$ is below the line. Is each of the following points above or below the line? i (2.5, 8.5) ii (-9, -15) iii (25, 65) iv (-20, -70) 5 The equation of a line is $y = 5x$. a Copy and complete this table of values for the function $y = 5x$. | x | -2 | -1 | 0 | 1 | 2 | 3 | 4 | | --- | --- | --- | --- | --- | --- | --- | --- | | y | | | | | | | | b Draw a graph of $y = 5x$. 6 This graph converts between US dollars (US$) and Hong Kong dollars (HK$). a How many Hong Kong dollars can you get in...