Question

Louis bought a burger and soda for $8. Kate purchased a slice of pizza and soda for $9. David purchased a burger, a slice of pizza, and a soda for $13.50. Write equations for each purchase. Solve your equations to find the cost of a burger, slice of pizza and a soda.

Answer 1

a). 8=b+s.....equation 1

9=p+s.....equation 2

13.5=b+p+s.....equation 3

b). The cost of pizza,p=$5.5

The cost of burger,b=$4.5

The cost of soda, s=$3.5

Explanation:

a). The equations for the total amount spent by each individual are as follows;

Total amount Louis used=Burger cost+Soda cost

Let Burger cost=b,

Soda cost=s

Replacing;

8=b+s.....equation 1

Total amount Kate used=Pizza cost+Soda cost

Let Pizza cost=p,

Soda cost=s

Replacing;

9=p+s.....equation 2

Total amount David used=Burger cost+Pizza cost+Soda cost

Let Pizza cost=p,

Soda cost=s

Burger cost=b

Replacing;

13.5=b+p+s.....equation 3

All the equations are as follows;

8=b+s.....equation 1

9=p+s.....equation 2

13.5=b+p+s.....equation 3

b).Replace the value of p+s in equation 3 with 8 from equation 1;

13.5=b+9

b=13.5-9=4.5, b=4.5

Replace value of b in equation 1 with 4.5;

8=4.5+s

s=8-4.5=3.5, s=3.5

Re[lace values of b and s in equation 3 with 4.5 and 3.5 respectively'

13.5=4.5+p+3.5

13.5=p+8

p=13.5-8=5.5, p=5.5

The cost of pizza,p=$5.5

The cost of burger,b=$4.5

The cost of soda, s=$3.5