Question 1082298
40c+20p = 130
8c+5p = 28 multiply all terms in this equation times -4 and add to the other equation:
40c+20p = 130
-32p+-20p = -112
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8c+0p = 18
8c = 18
c = 2.25 so the coffee is 2.25. Plug this into one of the two original equations and find p:
40c+20p = 130
40(2.25)+20p = 130
90+20p = 130
20p = 40
p = 2 the pastries are $2 each
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Try the other equation just for giggles:
8c+5p = 28
8(2.25)+5p = 28
18+5p = 28
5p = 10
p = 2 as you see, the pastries are still $2 ;-)