How do you solve the following linear system #4x - 3y = -5 , 4x +- 4y = -4 #?

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Answer 1 · 2016-02-28T04:28:46

For equations #4x-3y=-5# and #4x+4y=-4#, solution #(-8/7, 1/7)#
For equations #4x-3y=-5# and #4x-4y=-4#, solution #(-2, -1)#

We will use #color(blue)("method of elimination of variables")#

For equations #4x-3y=-5# and #4x+4y=-4#

#4x+4y=-4#
#4x-3y=-5#

Perform subtraction to obtain

#7y=1#

then #y=1/7#
Using #4x+4y=-4# and #y=1/7#

We have, #4x+4(1/7)=-4#

#x+1/7=-1#

#x=-8/7#

For equations #4x-3y=-5# and #4x+4y=-4#, solution #(-8/7, 1/7)#

Again, we will use #color(blue)("method of elimination of variables")#

For equations #4x-3y=-5# and #4x-4y=-4#

#4x-4y=-4#
#4x-3y=-5#

Perform subtraction to obtain

#y=-1#

then #y=-1#
Using #4x-4y=-4# and #y=-1#

We have, #4x-4(-1)=-4#

#x-(-1)=-1#

#x+1=-1#

#x=-2#

For equations #4x-3y=-5# and #4x-4y=-4#, solution #(-2, -1)#
graph{(4x-3y+5)(4x+4y+4)(4x-4y+4)=0 [-3, 2, -5, 5]}

God bless....I hope the explanation is useful..