#x#-intercept:
To find the #x#-intercept, substitute #0# for #y# and solve for #x#:
#4x = -1/2y - 1# becomes:
#4x = (-1/2 xx 0) - 1#
#4x = 0 - 1#
#4x = -1#
#(4x)/color(red)(4) = -1/color(red)(4)#
#(color(red)(cancel(color(black)(4)))x)/cancel(color(red)(4)) = -1/4#
#x = -1/4#
The #x#-intercept is: #-1/4# or #(-1/4, 0)#
#y#-intercept:
To find the #y#-intercept, substitute #0# for #x# and solve for #y#:
#4x = -1/2y - 1# becomes:
#(4 * 0) = -1/2y - 1#
#0 = -1/2y - 1#
#0 + color(red)(1) = -1/2y - 1 + color(red)(1)#
#1 = -1/2y - 0#
#1 = -1/2y#
#1 xx color(red)(-2) = 1/-2y xx color(red)(-2)#
#-2 = 1/color(red)(cancel(color(black)(-2)))y xx cancel(color(red)(-2))#
#-2 = y#
#y = -2#
The #y#-intercept is: #-2# or #(0, -2)#