In football, what doesa substitute do?
Takes the place of another player
4a + 3
a = 5
4(5) + 3
6a + 5
when a = 3
5a − 2b
when a = 6, b = 4
= 22
5(6) − 2(4)
4x − 3y
when x = 7, y = 5
= 13
6m − 4n
when m = 5, n = 3
= 18
7p − 3q
when p = 4, q = 5
3c + 5d
when c = 8, d = 2
= 34
10h − 4g
when g = 7, h = 3
= 2
a2 − 2b
when a = −4, b = 3
Hiring a bike costs C pounds, where C = 8 + 3h and h is the number of hours. How much does it cost to hire a bike for 5 hours?
v = u + at. Work out v when u = 4, a = −2 and t = 5.
When x = −2, which is bigger: x2 or 2x?
Work out 4k2 and (4k)2 when k = 3. Why are they different?
Work out the value of 5p − 2q when p = 4 and q = 3.
Work out the value of x2 + 3y when x = −5 and y = 2.
Theo works out 3m2 when m = 2 and gets 36. Find the right answer.
