How do we work out the asymptotes of the graph y=1/x -5

In most core 1 papers this kind of question is usually asked. First of all an asymptote is a line that is close to an axis but never touches it. Now look at the graph as a normal reciprocal graph of y=1/x the only difference now is that it has -5 added to the end. Draw the graph y=1/x and move it down the y-axis 5 spaces. This will be your y=1/x -5. You can then work out the x-intercept which would be 2/5. What you will see is two asymptotes along the y and x axis. The asymptote along the y-axis must be x=0 as that asymptote hadn't changed from the previous y=1/x graph. However, the asymptote along the x-axis has changed, since we moved the graph down 5 spaces along the y-axis, the asymptote must be y=-5. 

AB

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