 Modelling linear relationships - graphs

Interactive practice questions

Gas costs a certain amount per litre. The table shows the cost of various amounts of gas.

 Number of litres ($x$x) Cost of gas ($y$y) $0$0 $10$10 $20$20 $30$30 $40$40 $0$0 $16.40$16.40 $32.80$32.80 $49.20$49.20 $65.60$65.60
a

Write an equation linking the number of litres of gas pumped ($x$x) and the cost of the gas ($y$y).

b

How much does gas cost per litre?

c

How much would $47$47 litres of gas cost at this unit price?

d

In the equation, $y=1.64x$y=1.64x, what does $1.64$1.64 represent?

The unit rate of cost of gas per litre.

A

The number of litres of gas pumped.

B

The total cost of gas pumped.

C

The unit rate of cost of gas per litre.

A

The number of litres of gas pumped.

B

The total cost of gas pumped.

C
Easy
Approx 4 minutes

A diver starts at the surface of the water and begins to descend below the surface at a constant rate. The table shows the depth of the diver over $5$5 minutes.

There are $20$20 litres of water in a rainwater tank. It rains for a period of 24 hours and during this time, the tank fills up at a rate of $8$8 Litres per hour.

A baseball is thrown vertically upward by a baseball player when he is standing on the ground, and the velocity of the baseball $V$V (in feet per second) after $T$T seconds is given by $V=120-32T$V=12032T.

Outcomes

9D.AG3.03

Describe the meaning of the slope and y-intercept for a linear relation arising from a realistic situation and describe a situation that could be modelled by a given linear equation

9D.LR3.01

Determine values of a linear relation by using a table of values, by using the equation of the relation, and by interpolating or extrapolating from the graph of the relation

9D.LR3.03

Determine other representations of a linear relation, given one representation