# Question #84641

##### 1 Answer

6 hours

#### Explanation:

Notice that the line intercepts the bottom axis at 9 and also the side axis at 9.

This condition is means that the value you select for one axis relates to the same value on the other axis.

Thus 3 hours watching TV relates to 6 hours sleeping.

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One of the standardised forms for the equation of a strait line is:

where

By observation the y-intercept is 9

So we now have:

We need the value of