find the x and y intercepts for the line 9x-3y=-18

Question

need help

Answer 1

For y-intercept, plug in x=0 into the equation. 

 

9(0) + 3y = -18

 

3y = -18

 y = -6

 

Therefore, the y-intercept is y=-6.

 

As a coordinate point, it will be  (0, -6).

 

 

Also, the x-intercept as a coordinate point will be  (-2, 0).

 

Answer 2

Math involves definitions, formulas, and procedures.  These combine so that problems may be stated exactly and solved systematically.

With an X-Y coordinate system (an X axis and a Y-axis), the point at which a function crosses the X axis is called the “X intercept” (a definition).  This happens when the value of Y=0 (all points on the X axis have Y=0).  Now you should be able to state the definition of “Y intercept” and tell when that happens.

So (for X intercept), Y=0 and when Y=0,  9X = -18.      This means that X = -2.

Now, you find the Y intercept! (be very careful to notice the + and – signs in the formula).