solve by substitution

solve by substitution

1

(-5, -1)

2x – y = -9

3x – 8y = -7

7 4

2 6) x ybx ya) (4x3y5)3

2

9 1564x y5

2

xy

Simplify

3

Solve for x: 4 7 511 2x x

4119

x

4

A caterer is planning a party for 232 people. The customer has £808 to spend. A £32 pan of pasta feeds 8 people and a £36 sandwich tray feeds 12 people. How many pans of pasta and how many sandwich trays should the caterer make?

p = 14

w = 1032p + 36w = 8088p + 12w = 232

14 pans of pasta

10 sandwich trays

p = no. of pans of pastaw = no. of trays of sandwiches

5

Solve for x:5(x + 2) – 2(3 – 2x) = 3

19

x

6

Solve for x:x(2x + 1) – 2(x + 1) = 2x(x – 1)

x = 2

7

Solve for x: 5 114 12x

1511

x

8

The bill for 3 Big Macs and 2 Cokes is 20 CHF. The bill for 7 Big Macs and 8 Cokes is 55 CHF. What would be the bill for 2 Big Macs and 1 Coke?

b = 5 CHF

c = 2.5 CHF

3b + 2c = 20

7b + 8c = 55

2 Big Macs and 1 Coke would cost 12.50 CHF.

b = cost of 1 Big Macc = cost of 1 Coke

a) 7-1 + 70

25)2

b

Simplify

87

425

9

10

Solve for x: 2 5 41

xx

16

x

11

(-2, 1) 5x – y = -11 4x + 12y = 4

solve by substitution

12

Travis collects only 50-cent and $1 coins. His collection consists of 43 coins and their total value is $35. How many of each coin type does he have?

He has 16 50¢ coins and 27 $1 coins

13

2x + 7y = 2

3x + 5y = -8

solve by elimination

(-6, 2)

14

If p = 4, q = -2 and r = 3 find the value of

5r – 4q

23

15

George is 10 years older than Jane. Three years ago Jane was ¾ as old as George. How old is George now?

George is 43 years old.

22

3

2) xby

16

62) cad

6

6

64cd

6

44yx

Simplify

Write without brackets or negative exponents

a) (2a)-1

b) ab-1

12a

ab

17

Write as powers of 2, 3, or 51)4

a 1)27x

b 5) 125 5c =2-2 =3-3x =5-2

18

19

4x = 8

32

x

Solve for x.

solve by elimination

20

3x + 2y = 229x – 8y = -4

(4, 5)

21

2 193

x

32

x

Solve for x.

22

Your family is planning a 10 day trip to California. You estimate that it will cost $480 per day in Los Angeles and $380 per day in San Diego. Your total budget for the 10 days is $4200. How many days should you spend in each location?

a = 4

d = 6a + d = 10480a + 380d = 4200

4 days in Los Angeles

6 days in San Diego

a = no. of days in Los Angelesd = no. of days in San Diego

23

11 322

x

54

x

Solve for x.

24

If p = 4, q = -3 and r = 2 evaluate

2 2p q

5