# Applications Using Direct Variation

## Key Questions

Direct variation in real life.

#### Explanation:

1. A car travels $x$ hours with a speed of $\text{60 km/h}$ $\to$ the distance: $y = 60 x$

2. A man buys $x$ bricks that cost $1.50 each $\to$the cost: $y = 1.50 x$3. A tree grows $x$months by $\frac{1}{2}$meters each month $\to$the growth: $y = \frac{1}{2} x$• A good question Suppose we have to pay up the parking bill at a mall ON THE BILL BOARD IT SAYS |________| | $$ FOR A 4 HOUR PARKING YOU HAVE TO PAY$3.24


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$$  AND UNDER IT A LED SAYS YOU HAVE BEEN HERE FOR (5HRS)


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|_________

now what would you do

you would use direct variation

let me make a table

let x be the cost

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hours parked __ cost

$$4                                       |                      $3.24  5 | $x$$\frac{3.24 \cdot 5}{4} = x$solving for $x$you will get $4.05\$