1) 4*a* + 3*b* = 11

2*a* + 3*b* = 7

2) 2*c* + 3*d* = 26

5*c* – 3*d* = 2

3) 4*e* + 3*f* = 15

2*e* – *f* = 5

4) 2*x* + *y* = 10

*x* + 2*y* = 11

5) 3*a* – 4*b* = 7

*a* + 2*b* = 9

6) 10*c* – *d* = 13

5*c* – 3*d* = -11

7) 6*x* – y = 9

4*y* – 3*x* = -15

8) 3*g* – 1 = 2*h*

17 – 2*g* = *h*

9) ½ *j* + 2*k* = 8

*j* + 7*k* = 25

10) 16 – 4*m* = 2*n*

18 – 2*m* + 4*n* = 0

11)

12) I own a shop. On one day I sell 5 caps and 3 watches for £60. On another day, I sell 3 caps and 2 watches for £38.

a) Write an expression for each of the days; let *c* be the number of caps that I sell, and *w* be the number of watches that I sell.

b) Find out how much a cap and a watch cost.

13) I am a baker. On Monday it takes me 71 minutes to make 3 flapjacks and 5 cakes. On Tuesday it takes me 89 minutes to make 7 flapjacks and 4 cakes.

a) Write an expression for Monday and Tuesday. Let *f* be the number of flapjacks and *c* be the number of cakes.

b) Find how long it takes to make a flapjack and how long it takes to make a cake.

c) How long would it take for me to make 8 flapjacks and 11 cakes? Give your answer in terms of minutes.