a tour group split into two groups when waiting in line for food at a fast food counter. The first group bought 8 slices of pizza and 4 soft drinks for $29.40 . the second group bought 7 slices of pizza and 6 soft drinks for $30.30. how much does one slice of pizza cost ?
+130536 Let P be the cost of a pizza slice and S be the cost of a soft drink.....and we have this system...
8P + 4S = 29.40
7P + 6S = 30.30 multiply the first equation by 6 and the second by -4 and we have
48P + 24S = 176.40
-28P - 24S = -121.20 add these equations
20P = 55.20 divide both sides by 20
P = $2.76
