The cost of 6 sandwiches and 4 drinks is $53 cost of 4 sandwiches and 6 drinks is $47. How much does one sandwich cost?

The volume of a box varies directly with its length if a box in the group has a length of 30inches and k=24 what is its volume

Martha is training for a duathlon, which includes biking and running. she knows that yesterday she covered a total distance of over 55.5 miles in more than than 4.5 hours of training. martha runs at a speed of 6 mph and bikes at a rate of 15.5 mph.

7x^2-9x+5=0 find the discriminant and number of real solutions