Write the equation in slope-intercept form and then graph it.
Practice makes perfect
Let's first write the equation in slope-intercept form and then graph it.
Write The Equation
To write the equation in slope-intercept form, we need to know the slope and y-intercept. We are told that, to rent a truck, Morwenna needs to pay a one-payment of $20. Therefore, the constant be 20.
b=20
Also, she pays $0.25 per mile. This value gives us information about the rate of change or slope. Thus, m=0.25. Now, when we know both the slope and y-intercept b, we can write the equation.
y=0.25x+20
Graph The Equation
To graph an equation, we need at least two points. Then we can draw a line through them. We already know that y-intercept is 20. This gives us the point (0,20). Using the slope, we can plot the second point. The slope is 0.25 but this is difficult to use on a coordinate plane. Let's rewrite it as a fraction.
m=0.25 ⇔ m=1/4
We will go one step 1 for every 4 steps to the right. Drawing the line through these points we get the graph of the equation.
Notice that this graph is restricted to only positive values because Morwenna cannot drive a negative number of miles.
