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

1 Answer
Aug 31, 2017

I have started you off

Explanation:

4x-3y=-5" "->" "y=4/3x +5/3" "..........Equation(1)

4x+4y=-4" "->" "y=-x-1" "............Equation(2)

4x-4y=-4" "->" "y=x+1" "................Equation(3)
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Using Equation(2) substitute for y in Equation(1)

y=-x-1" "->" "4/3x+5/3=-x-1

color(white)("dddddddddddd")->" "7/3x=- 8/3

color(white)("dddddddddddd")->" "x=-8/7

Thus y=-x-1" "->" "y=-(-8/7)-1 = +1/7

So intersection of Equation(1) and Equation(2) ->(x,y)=(-8/7,+1/7)
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You repeat this approach for

Eqn(2)->Eqn(3)

Then for

Eqn(1)->Eqn(3)

I will let you do those.
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Tony BTony B