How do you solve the system of equations #y= - 8x + 20# and #- 3x - 8y = 23#?

1 Answer
Jul 28, 2017

#x=3#
#y=-4#

Explanation:

Given -

#y=-8x+20# ---------------------- (1)
#-3x-8y=23# -----------------------(2)

Substitute #y=-8x+20# in equation (2)

#-3x-8(-8x+20)=23#
#-3x+64x-160=23#
#61x=23+160=183#
#x=3#

Substitute #x=3# in equation (1)

#y=-8(3)+20#
#y=-24+20#
#y=-4#