6.4
Solving Systems by Elimination
Using Multiplication
x - y = -8
7x + 5y = 16
6x + y = -39
3x + 2y = -15
{
2x - 3y = 0
3x - 2y = 5
-4x + 2y = 0
10x + 3y = 8
A personal aircraft traveling with the wind flies 520 miles in
4 hours.
On the return trip, the airplane takes 5 hours to travel the
same distance.
Find the speed of the airplane if the air is still.
rate
with the
wind
against
the wind
time
distance
r t = d
A fishing boat travels 10 miles downstream in 30 minutes.
The return trip takes the boat 40 minutes.
Find the rate in miles per hour of the boat in still water.
Choose your problem
Level A
{
x+y = 2
2x - y = 7
Level B
{
y - x = 17
2y + 3x = -11
Level C
{
1.5x - 6.5y = 3.5
0.5x + 2y = -3