To find the x- and y-intercepts of -3x-4y=18:
Two Separate problems to solve!!
1st To find the x-intercept:
Let y=0 and solve for x.
-3x-4*0=18
-3x=18
x=18/-3
x=-6 --> x-intercept is (-6,0)
2nd To find the y-intercept:
Let x=0 and solve for y.
-3*0-4y=18
-4y=18
y=18/-4
y=-9/2
y=-4.5 --> y-intercept is (0, -4.5)
To graph, plot the x- and y-intercepts and draw the line!!
You should also choose an x- or y-value, substitute into the original to find a check point. If your x- and y-intercepts are correct, the point will lie on the line.
Example: If we let x=1, then
-3*1-4y=18
-3-4y=18
-4y=21
y=21/-4
y=-5 1/4
y=-5.25 --> (1, -5.25) should lie on the line drawn using the intercepts
Espero que ayuda <3
