Solve the system of linear equations

[frctl]

Yes I am no longer adding.

I have:
40x₁+ 30x₂= 24
40x₁ + 30x₂ = -28

What operation can I take?

 

[Deleted member 4993]

Yes I am no longer adding.

But if you did add - what should you have obtained as "result"?

 

[frctl]

80x₁ + 60x₂ = -4

 

[Deleted member 4993]

80x₁ + 60x₂ = -4

Now it is correct!

Let's now think about a different operation. Instead of adding two equations [ equations (1) & (2)]

if you subtract equation (2) from equation (1) - what do you get?

 

[frctl]

40x₁+ 30x₂= 24
40x₁ + 30x₂ = -28
Subtract equation 2 from 1
= -52

 

[Deleted member 4993]

40x₁+ 30x₂= 24
40x₁ + 30x₂ = -28
Subtract equation 2 from 1
= -52

You are making the same mistake that you made in your response #9.

You are writing an equation with "=" and right-hand-side, without "writing" a left-hand-side!!

Please correct it.

 

[frctl]

x₁ + x₂ = -52

 

[Deleted member 4993]

x₁ + x₂ = -52

Incorrect ..... do the subtractions carefully!

 

[frctl]

40x₁ - 40x₁ and 30x₂ - 30x₂ cancel out and (-28)-(24) = -52

 

[Deleted member 4993]

40x₁ - 40x₁ and 30x₂ - 30x₂ cancel out and (-28)-(24) = -52

When those cancel out - what remains on the Left-hand-side?

 

[frctl]

0 = -52

what does this mean?

 

[Deleted member 4993]

0 = -52

what does this mean?

Do you see the similarity between this problem (equations) and the problem posted by you at:

https://www.freemathhelp.com/forum/...ne-points-of-intersection.117647/#post-463858

 

[frctl]

Yes, this means they are two parallel lines with no intersection

 

[Deleted member 4993]

Yes, this means they are two parallel lines with no intersection

Correct.

That means there is "No solution".

 

[Otis]

Hi frctl. Please post the complete title, author name(s) and publisher's name of the textbook that you're using. Thanks!

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