Part of MathsStraight line graphs
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A short video showing how to draw inverse proportion.
Click to see a step-by-step slideshow.
WHAT YOU NEED: 12 cubes, a pen and a ruler.
STEP 1: Use the ruler to draw a vertical line, then draw a horizontal line directly from the end of the vertical line.
STEP 2: Stack 12 cubes along the vertical line and mark the top right corner of the top cube with a cross...
...rearrange the cubes so you have two stacks of six cubes. Mark the top right corner of the outer stack with a cross...
...rearrange the cubes so you have three stacks of four cubes. Mark the top right corner of the outer stack with a cross.
...rearrange the cubes so you have four stacks of three cubes. Mark the top right corner of the outer stack with a cross...
...rearrange the cubes so you have six stacks of two cubes. Mark the top right corner of the outer stack with a cross. Rearrange the cubes so you have 12 cubes in a horizontal row and mark the top right corner of the outer stack with a cross.
STEP 4: Remove the cubes. Join the crosses with a smooth curve. This is a graph of the function y = 12/x. Inverse proportion leads to curved graphs like this that get closer and closer to the x and y axes without ever touching them..
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