How do you solve 4x + 5y = 11 and y = 3x - 13?

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Answer 1 · 2015-10-14T06:37:43

The solution is
#x=4,y=-1#

#4x + 5y = 11 #...equation #1#
#y =color(blue)( 3x - 13#....equation #2#

Solving by substitution :

Substituting equation #2# in #1#

#4x + 5y = 11 #
#4x + 5color(blue)(( 3x - 13) = 11 #

#4x + 15x - 65 = 11 #

#19x = 11+65 #

#19x = 76#

#x=76/19#

#color(blue)(x=4#

Finding #y# by substituting #x# in equation #2#:

#y = 3x - 13#

#y = 3*4 - 13#

#y = 12 - 13#

#color(blue)(y=-1#