A line can be described algebraically using the slope intercept form, The slope intercept form is written: y=mx + b

m= slope

b= y intercept

An example question may look like this.

**Put the following in slope intercept form**

**Put the following in slope intercept form**

**Find the x-intercept and y intercept for the following line.**

**-x + 2y =10**

**Step 1**** In order to find the x intercept plug 0 in for y -x+2(0) =10**

**Step 2 ****-x+0=10**

**Step 3**** -x = 10**

**Step 4 ****x=-10**

**In order to find the y intercept plug 0 in for x**

**Step 1.**** 0-2y =10**

**Step 2.**** 0 +2y =10**

**Step 3.**** y =5**

Point Slope Form

The Point Slope Form is used when a point on the line ( x1,y1) is given or known and the slope, m

m= slope

Write the equation of a line with a slope of 1/2 containing the points (6,-4)?

Horizontal Line Form:

y = 2 (* This number is a constant and is where the line crosses the y axis)*

The slope of a horizontal line is zero. They have horizontal change but the vertical change is zero. The rise/run formula for slope always yields zero since rise = 0.

y = mx + b

y = 0x + 2

y = 2

Vertical Line Form:

x = -2 (or any number)

Lines that are vertical have no slope.

They have "rise", but no "run". The rise/run formula for slope always has a zero denominator and is undefined.

# What is a linear equation?

## Slope of a Line

**Step 1**. Subtract -3x from each side

**Step 2** -2y= -3x +8 Isolate y by dividing by 2

**Step 3**. y = -3x/-2 + 8/-2 simplify 8/-2 = -4

**Step 4** y = 3/2x -4

**Step 1**. Subtract 7x from each side

**Step 2** 9y= 7x+27 Isolate y by dividing 9

**Step 3**. y = 7x/9 + 27/9 simplify 27/9 =3

**Step 4** y = 7/9x +3