Download 3.4 Applications of Systems of Linear Equations

Concepts 1, 4, 5
3.4.1
 John
Involving Cost
and Amy bought school
supplies. John spent $10.65 on
4 notebooks and 5 pens. Amy
spent $7.50 on 3 notebooks and
3 pens. What is the cost of 1
notebook and 1 pen?
3.4.4 Involving Distance
 A plane
flies 660 miles from
Atlanta to Miami in 1.2 hours when
traveling with a tailwind. The
return flight against the same wind
take 1.5 hours. Find the speed of
the plane in still air and the speed
of the wind.
 D = rt
3.4.5 Involving Geometry
 Two
angles are supplementary.
The measure of one angle is 16˚
less than three times the measure
of the other. Find the measure of
the angles.
Involving Cost
 Suzy
has a piggy bank consisting
of nickels and dimes. If there are
30 coins worth $1.90, how many
nickels and dimes are in the
bank?
 Answer: 22 nickels, 8 dimes
Involving Distance, Rate, Time
 It
takes a pilot 1.75 hours to travel with
the wind to get from Jacksonville to
Myrtle Beach. Her return trip takes 2
hours flying against the wind. What is
the speed of the wind and the speed of
the plane in still air if the distance
between Jacksonville and Myrtle Beach
is 280 miles?
 Answer: Plane 150 mph, wind 10 mph
Involving Distance, Rate, Time
 Nikki
and Tatiana rollerblade in
opposite directions. Tatiana
averages 2 mph faster than Nikki.
If they began at the same place
and ended up 20 miles apart after
2 hours, how fast did each of them
travel?
 Answer: Nikki 4 mph, Tatiana 6
mph
Involving Geometry
 Two
angles are complementary.
One angle measures 6˚ more than 5
times the measure of the other.
What are the measure of the two
angles?
 Answer: 76 and 14 degrees
Distance

A car and a truck leave cities 460 miles
apart, traveling toward each other. The
car travels 15 miles per hour faster than
the truck. They pass one another 4
hours later. What are their speeds?

Answer: truck 50 mph, car 65 mph
Cost

Elle went to Pet Smart and bought 4
goldfish and 3 turtles for $28. Later that
day, Warren went to Pet Smart and
bought 6 goldfish and 1 turtle for $10.
How much does 1 goldfish cost?

Answer: goldfish are $0.14 and turtles
are $9.16