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I dont even know how to explain this, but please help

I dont even know how to explain this, but please help-example-1
User MyBoon
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1 Answer

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Both Px + Qy = R and Tx + Uy = V have the same solution (2, 9), meaning the point (2, 9) lies on both lines such that x = 2 and y = 9 makes both equations true.

When you add these equations together, you get

(Px + Qy) + (Tx + Uy) = R + V

โ†’ (P + T ) x + (Q + U ) y = R + V

so the first option is equivalent.

When you subtract the first equation from the second, you get

(Tx + Uy) - (Px + Qy) = V - R

โ†’ (T - P) x + (U - Q) y = V - R

so the third option is also equivalent.

User Ali Doustkani
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