The x-intercept is obtained by solving the equation
y=-(2/3)x-4 substituting y=0 (i.e. where line cuts y=0)
0=-(2/3)x-4 =>
(2/3)x=-4
multiply by 3 on both sides
(2/3)x*3=-4*3
2x=-12
divide by 2 on each side
x=-6 [x-intercept]
Check: y(-6)=-(2/3)(-6) -4=4-4=0 good!
