Tommy bought a total of 30 apples and oranges for a classic picnic. Apple's cost $3 per pound and oranges cost $4 per pound. Tommy spent $100 total. How many apples and oranges did Tommy buy?

Please show work and explain​

Respuesta :

Solution: (20,10) Tommy bought 20 apples and 10 oranges.

Step-by-step explanation:

x+y=30: y=30-x

3x+4y=100

3x+4(30-x)=100

3x+120-4x=100

-1x +120=100

     -120   -120

-1x=-20

/-1   -1

x= 20

20+y= 30

-20     -20

y=10

20+10=30

You solve this equation using substitution