how do you graph linear functions ?

Question

g(x)=x+7  i dont know how to graph it :/ 

Answer 1

g(x) = x + 7 is a linear equation in Slope-Intercept form. The coefficient of the x (1 in this case) represents the slope of the line and the 7, represents the y-intercept, so it actually represents the point (0,7).

 

Lines with positive slope rise as you move from left to right. The fact that the slope of the line is 1 means that the absolute value of the x-intercept will always be equal to the absolute value of the y-intercept. So the line also passes through the point (−7,0).

 

Two points completely determine a line, so just draw the line through (0,7) and (−7,0).

Answer 2

All you need to graph a line is two points on the line. Once you have two points, use a straight edge to draw the line passing through the two points.

 

To get two points, simply pick a value for x, then plug that value into your linear equation to compute the y value.  I'll do one of the points for you:

 

g(x) = y = x + 7

 

Let's pick x = 1:

y = x + 7

y = 1 + 7    [Plugged x=1 into the equation]

y = 8

 

So one of your points is (1,8).  To find a second point, pick a different value of x, say x = 5, and plug it into the equation (y = x+7) to find the y-value.