Easy Algebra Step-by-Step

186 Easy Algebra Step-by-Step

Step 4. Plot the two points and draw the line through the points.

–2

4

2

5

(1, 1)

(0, –1)

x

y

y = 2 x – 1

Graphing a Linear Equation That Is in Slope-y-Intercept Form

When the equation is in slope-y-intercept form, mmmmxbx , the number m is

the slope, and the number b is the y value of the point on the line where it

crosses the y-axis. Hence, b is the y-intercept. The x value for the intersec-

tion point is always x= 0. In that case, you actually need to calculate only

one y value to draw the line.

Problem Graph the line whose equation is yx 31 xx+.

Solution

Step 1. Substitute a value for x other than 0 and compute the corresponding

y value.

When x= 1 , y= 3 (()+ 14 =.