30 likes | 228 Views
Section 7.4: Applications with Linear Systems. A hardware store orders a shipment of two types of hammers for $168. One type of hammer costs $3; the other type of hammer costs $5. If the store ordered 40 hammers in all, how many of each type were ordered? x =$3 hammer y =$5 hammer.
E N D
A hardware store orders a shipment of two types of hammers for $168. One type of hammer costs $3; the other type of hammer costs $5. If the store ordered 40 hammers in all, how many of each type were ordered? • x=$3 hammer • y=$5 hammer 1st equation is the money 2nd equation is always x+y=how many There are 24 - $5 hammers and 16 - $3 hammers.
2. With a given head wind, a certain airplane can travel 3600 km in 9 h. Flying in the opposite direction with the same wind blowing, the airplane can fly the same distance in 1 h less time. Find the speed of the airplane in still air and the wind speed. X= plane speed Tailwind 8 (x+y) 3600 Y= wind speed Faster Slower Headwind 9 (x-y) 3600 Here is a trick instead of distributing The plane speed is 425 km/hr The wind speed is 25 km/hr But what does this mean?