Answer:
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Given system:
- 8x - 3y = 12,
- - 8x + 3y = 5.
We see constants are same with opposite sign.
To make them same multiply both sides of the second equation by -1:
- ( -1 )( -8x + 3y) = ( - 1)*5 ⇒ 8x - 3y = - 5
Now we have two equations with same left sides but different right sides:
This is false and hence the system has no solution.