Find the intercepts of -2x-3y=18 and graph

Answer 1

For the intercepts, the formula is : x/a + y/b = 1

So, to convert the given line into this form, we need to first divide both L.H.S and R.H.S with 18

-2x - 3y = 18

-2x/18 - 3y/18 = 1

-x/9 -y/6 = 1

x/-9 + y/-6 = 1 { Take (-) on the denominator, to get into the form x/a + y/b = 1 }

So, now we have it in the form x/a + y/b = 1.

So, a is called X-intercept, which is the denominator of x and

b is called the Y-intercept which is the denominator of y.

Hence, we have X-intercept, a = -9 and Y-intercept, b = -6.

In general, To get the graph we need two points (x,y).

For X-intercept, we have y = 0 and for Y-intercept, we have x = 0.

So, the points we get here are, A(-9,0) and B(0,-6)

assuming these two points as : (x1,y1) (x2,y2)

To point A :- If x1 is negative, it is on left side of the x-axis and as y1=0, it is on the line of x-axis.

Similarly, To point B :- y2 is negative which is on the down side of y-axis and on the line of y-axis as x2=0.

Draw the graph, if you don't understand the graph theoretically , i am available to take the class on the entire pre-algebra class which is more interactive as it requires explanation of graphs.

Answer 2

To find the x-intercept, let y = 0 in the equation and solve the equation for x:

-2x - 3(0) = 18, so x = -9. The ordered pair for the x-intercept is then ( -9, 0 ).

For the y-intercept, let x = 0 in the equation and solve for y:

-2(0) - 3y = 18. Solving for y, we have y = -6. The ordered pair for the y-intercept is ( 0 , -6 ).

Now that you have these two points, the x-intercept will be plotted at -9 on the x-axis and the y-intercept will be plotted at -6 on the y-axis.