How do you find the x- and y-intercept of the line 4x – 7y = 84?

1 Answer
Apr 21, 2017

Answer:

See the entire solution process below:

Explanation:

y-intercept: Substitute #0# for #x# and solve for #y#:

#4x - 7y = 84# becomes:

#(4 * 0) - 7y = 84#

#0 - 7y = 84#

#-7y = 84#

#(-7y)/color(red)(-7) = 84/color(red)(-7)#

#(color(red)(cancel(color(black)(-7)))y)/cancel(color(red)(-7)) = -12#

#y = -12#

The y-intercept is #-12# or #(0, -12)#

x-intercept: Substitute #0# for #y# and solve for #x#:

#4x - 7y = 84# becomes:

#4x - (7 * 0) = 84#

#4x - 0 = 84#

#4x = 84#

#(4x)/color(red)(4) = 84/color(red)(4)#

#(color(red)(cancel(color(black)(4)))x)/cancel(color(red)(4)) = 21#

#x = 21#

The x-intercept is #21# or #(21, 0)#