Power of Maths: Paper 1 – Section 7 EXERCISE 5 1. The value V in euro of a car t years after its purchase is shown by the linear graph below:
50 000 V
35 000 40 000 45 000
€
15 000 20 000 25 000 30 000
10 000 5000 0 1 2 34 5 6 Years
If it cost € 50 000 new and its value after 5 years was € 30 000, fi nd: (a) the relationship between V and t, (b) when its value was € 20 000, (c) when its value was € 0.
2. A cable car starts its journey at 6000 m above the ground. It descends at 300 m per minute. Find an expression for its distance s in metres above the ground after t minutes. Use this expression to fi nd how long it takes to reach the ground.
3. For the points (x, y) given in the table below, investigate if y is a linear function of x. x
y
–8 –4 0 4 8 0
0⋅5 If it is linear, fi nd a formula for this relationship.
4. The populations of two countries A and B in millions from 1950 to 2000 are shown in the table below. 1950
