Question

witch method is being used, subtraction or elimination?



M=MP3 H=headphones



5x’s the cost of mp3 players + 8x’s the total of a set of headphones that = $840

5m+8h=840

3x’s the total cost of an mp3 + 4x’s the cost of a set of headphones = $480

3m+4h= 480

Equations

5m+8h=840

5m=840-8h

M=(1/5)*(840-8h)

3m+4h=480

3*(1/5)*(840-8h) +4h=480

3*(840-8h)+20h=2400

2520-24h+20h=2400

-4h=-120

H=30

M=(1/5)*(840-8h)

M=(1/5) *(840-8*(30))

M=(1/5)*(840-240)

M=(1/5)*(600)

M=120

Answer 1

Substitution. All the way.