Equations and Expressions

=Objective= In this lesson, we will cover variables, expressions, equations, and methods of manipulating them.

Methods of manipulation include simplifying, substituting, and solving.

=Key Terminology=

=Variables and Expressions =

=Equations=

A simple equation:

2a+3b+c = 0 This equation has 3 variables (a,b and c);; 3 terms (2a, 3b and c);; and this equation is an equality, because here is an equal sign (=) between both sides of the equation.

Next: solution to a simple algebra problem. Solve the following equation for (a):

$$\begin{align} 2a + 3a - 30 &= 10 \\ \phantom{2a + 3a }+30 &\phantom{=} +30 \\ 2a + 3a &= 40 \\ 5a & = 40 \\ \frac{5a}{5} &= \frac{40}{5} \\ a &= 8 \end{align}$$

- -- - - - - - - - -     Some trig stuff:

sin ɵ = Opposite-Side/Hypotenuse

cos ɵ = Adjacent-Side/Hypotenuse

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