Lectures and Quick Notes(1.2)
Chapter
Chapter 1
Section
Lectures and Quick Notes(1.2
Lectures 4 Videos
• Linear systems mean there are 2 or more equations, but typically 2, where there are more than 1 unknown.
Section Intro

## Isolating a variable for substitution method

ex From 6a + 5b = 12, isolate the variable a.

Therefore, a = 2 - \dfrac{5}{6}b

Isolating Variable when there are Two

Substitution method ex1

Solve for (x, y) when

 \displaystyle \begin{cases} x + y = 3 \\ 2x - y = -1 \end{cases} 

solution

 \displaystyle (x, y) = (\frac{2}{3}, \frac{7}{3}) 

2.47mins
Substitution method ex1

Substitution method ex2

Solve for (x, y) when

 \displaystyle \begin{cases} 3x + 10y = 12 \\ 2x - 7y = 2 \end{cases} 

solution

 \displaystyle (x, y) = (\frac{104}{41}, \frac{18}{41})