# Graph y=-x-20 y=-x-20
Use the slope-intercept form to find the slope and y-intercept.
The slope-intercept form is y=mx+b, where m is the slope and b is the y-intercept.
y=mx+b
Find the values of m and b using the form y=mx+b.
m=-1
b=-20
The slope of the line is the value of m, and the y-intercept is the value of b.
Slope: -1
y-intercept: -20
Slope: -1
y-intercept: -20
Any line can be graphed using two points. Select two x values, and plug them into the equation to find the corresponding y values.
Choose 0 to substitute in for x to find the ordered pair.
Replace the variable x with 0 in the expression.
f(0)=-(0)-20
Simplify the result.
Multiply -1 by 0.
f(0)=0-20
Subtract 20 from 0.
f(0)=-20
-20
-20
The y value at x=0 is -20.
y=-20
y=-20
Choose 1 to substitute in for x to find the ordered pair.
Replace the variable x with 1 in the expression.
f(1)=-(1)-20
Simplify the result.
Multiply -1 by 1.
f(1)=-1-20
Subtract 20 from -1.
f(1)=-21
-21
-21
The y value at x=1 is -21.
y=-21
y=-21
Create a table of the x and y values.
xy0-201-21
xy0-201-21
Graph the line using the slope and the y-intercept, or the points.
Slope: -1
y-intercept: -20
xy0-201-21
Graph y=-x-20     