Linear Equations-
A linear equation is simply an equation which ends up with one variable equal to a number.

With the variable on one side:

1. (3/7)x + 9 = 15	Write original equation.
2. (3/7)x = 6	Subtract 9 from each side.
3. x = (7/3)6	Multiply each side by 7/3, the reciprocal of 3/7.
4. x = 14	Simplify your answer.

With the variable on both sides:

1. 5n + 11 = 7n - 9	Write original equation.
2. 11 = 2n - 9	Subtract 5n from each side.
3. 20 = 2n	Add 9 to each side.
4. 10 = n	Divide each side by 2.

Literal equations-
A literal equation has more than one variable and has no numerical answer.
 

7x - 3y = 8	Write original equation.
-3y = -7x +8	Subtract 7 from each side.
y = (7/3)x - (8/3)	Divide each side by 3.

Equation of a line-
a. Given two points
    Given the points (-2,-1) and (3,4)

m = (y2 - y1)/(x2 - x1)	Write equation.
m = (4 - (-1))/(3 - (-2)	Substitute for variables x and y.
m = 5/5	Work it out.
m = 1	Simplify.

b. Slope Intercept Form
Given m= 3 and y intercept 5.

y = mx + b	Write slope intercept form.
y = 3m + 5	Substitute for variables.

c.  Point-Slope Form
Given point (-2,-1) and a slope of 1.
 

y - y1 = m(x - x1)	Write point slope form.
y - (-1) = 1( x - (-2))	Substitute for variables.
y + 1 = x + 2	Simplify.
y = x + 1	Write in slope intercept form.

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