Question 604444
    you order 2 tacos and 2 enchiladas for $4.80. you friend order 3 tacos and 1 enchiladas for $4. how much does each cost
.
Let t = cost of a taco
and e = cost of an enchilada
.
2t + 2e = 4.80
3t +  e = 4.00
.
multiply bottom equation by -2 and add both equations together:
 2t + 2e = 4.80
-6t - 2e = -8.00
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-4t      = -3.20
t = -3.20/(-4)
t = $0.80 (or 80 cents for a taco)
.
enchilada:
3t +  e = 4.00
3(0.80) +  e = 4.00
2.40 +  e = 4.00
e = 4.00 - 2.40
e = $1.60