Question 59955
5x + 2y = 5 

The replacement set is [(2, -2), (2, -7), (5, -4), (3, -5)}

At first input the first set of values, that is (2,-2) in the given equation,

==> 5*2 + 2*-2 = 10 + -4 = 6

That is the value we got while substituting  in the left side of the given equation is not same as the right side. 
 So (2,-2) is not a solution for the given equation.

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Now substitute the second pair of values in the given equation.

==> 5 * 2 + 2 * -7 = 10 + -14 = -4, which is again not equal to 5

so (2,-7) is not a solution

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Now take (5,-4)

==> 5 * 5 + 2 * -4 = 25 + -8 = 16,  which is again not equal to 5
so this is also not a solution for the given equation.

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Now take the pair of values, (3,-5)

==> 5*3 + 2*-5  = 15 + -10 = 5,  which is equal to the right side.  

so (3,-5) is the solution set of the given equation.

O.K
BYE.