Graphing Linear Equations
method.slope-interceptA is linear equationan equation which would produce the graph of
a line. Solving the equation for y would produce the slope-intercept equation of the
line. The form of this line would then be _{
},
where m is the slope and b is the y-intercept. Once the line is in this
form, recognize the coefficient of the x (the number in front of the x) as the slope and
the constant number (the number that is not in front of a either variable) as the
y-intercept.The following example shows how to solve a linear equation for the variable y: Solve the equation for y.
_{
}
…which means m = The line could then be easily graphed by first plotting the
y-intercept which is “b”. Think of “b” as the _{
} think of “m” as how to ove to the next point from the y-intercept. The numerator (top number) of the slope tells how many units to move vertically (up or down depending on whether the number is positive
or negative) and the denominator (bottom number) of the slope tells you how many units to
move horizontally (right or left depending on whether the number is positive or negative). Since the slope in the example above is m_{
},
then from (0,-4) move up two units
and to the right 3 units, plotting the point (3,-2). Moving another 2 units up and 3 units
to the right, plot the third point (0,6). Now
that three co-linear points have been plotted, using a straight-edge draw a line through the points
with arrows at the ends of the line indicating that there are many points (solutions) on
that particular line.The views and
opinions expressed in this page are strictly those of Mary Lou Baker. This page was edited on 09-Jan-2014 |