How do you solve the system # y=6x - 11# and #-2 - 3y = -7# by substitution?

1 Answer
May 25, 2015

Given
#"[1] "y=6x-11#
#"[2] "-2-3y = -7#

from #"[1]"# we can substitute #6x-11# for #y# in #"[2]"#
#"[3] "-2-3(6x-11) = -7#

#"[4] " -3(6x-11) = -5#

#"[5] " 6x-11 = 5/3#

#"[6] " 6x = 38/3#

#"[7] " x = 19/9#

Note that #"[2]"# can be solved directly for #y#
#"[8] "-3y = -5#

#"[9] " y = 5/3#

Query: Was the second equation intended to be
#-2x-3y = -7#?