Fri,Nov,13/09

Systems Of Equations: We reveiewed these.
-have 2 equations and 2 variables
-points of intersection
-parallel lines=no solution
-could overlap=infinate # of solutions
-to solve them; graph, substitution, or adding/subtraction

We were shown Tut 3.5 on page 149 of the text
Steps to Solve reduce system to 1 variable
Solve the equation
substitute and solve for other variable

ex 1 x=her speed y=river speed
Equations x+y=10
x-y=6
Solve (2x=16) /2

Find Other Equation x+y=10
8+y=10
y=2

x=8 y=2 Final Answer (8,2) Her speed =8km and river speed =2km.

We were given an assignment on page 153 #1ac,2b, 3, 4, & 7