SOLUTION: the spanish class was having a fiesta for the end of the year and they ordered tacos from a local restaurant. The tacos cost $.60 each and the enchiladas cost $1.25 each. They orde

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Question 612338: the spanish class was having a fiesta for the end of the year and they ordered tacos from a local restaurant. The tacos cost $.60 each and the enchiladas cost $1.25 each. They ordered 15 more than enchiladas and the total bill was $64.50. how many of each did they order?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = number of enchilada's ordered
Let +b+ = number of tacos ordered
given:
+1.25a+ = cost of enchilada's
+.6b+ = cost of tacos
----------------
(1) +1.25a+%2B+.6b+=+64.5+
(2) +b+=+a+%2B+15+
Substitute (2) into (1)
(1) +1.25a+%2B+.6%2A%28+a+%2B+15+%29+=+64.5+
(1) +1.25a+%2B+.6a+%2B+9+=+64.5+
(1) +1.85a+=+64.5+-+9+
(1) +1.85a+=+55.5+
(1) +a+=+55.5+%2F+1.85+
(1) +a+=+30+
and, since
(2) +b+=+a+%2B+15+
(2) +b+=+45+
They ordered 30 tacos and 45 enchiladas
check:
(1) +1.25%2A30+%2B+.6%2A45+=+64.5+
(1) +37.5+%2B+27+=+64.5+
(1) +64.5+=+64.5+
OK