Question

2 regular pizzas and 3 small pizzas cost £22 6 regular pizzas and 12 small pizzas cost £78

find the cost of one each ​

Answer 1

small $3.4 regular $6.2

Explanation:

2r +3s = 22.6

6r *12s = 78

Multiply the first by -3

-6r -9s = -67.8

6r +12 s = 78

Add both (6r will be cancelled)

3s = 10.2

s = 3.4 small = 3.4 (3 small = 10.2)

2r +10.2 = 22.6

2r = 12.4

r = 6.2

Answer 2

Regular pizza: £5

Small pizza: £4

Explanation:

Let x = regular pizza

Let y = small pizza

6x + 12y = 78

2x + 3y = 22

I'm going to use elimination method to solve for y

6x + 12 y = 78

-3(2x + 3y = 22) = -6x -9y = -66

Eliminate the x

3y = 12

Divide both sides by 3

3y/3 = 12/3

y = 4

Substitute the y in one of the original equations

2x + 3(4) = 22

2x + 12 = 22

Subtract both side by 12

2x + 12 - 12 = 22 - 12

2x = 10

Divide both sides by 2 to solve for x

2x/2 = 10/2

x = 5