Question

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

Answer 1

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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