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What is x and y equal to?

-10x + 4y = -14

7x + 5y = 2

User Gnuwings
by
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1 Answer

6 votes

Answer: x =1, y = -1

Explanation:

-10x+4y=-14

7x+5y=2

Let's eliminate y.

5(-10x+4y= -14)

4(7x + 5y=2)

[ I multiplied the first equation by the coefficient of y in the second equation and did the same in the second equation].

=> -50x+20y =-70

28x+20y = 8

Notice how the coefficients of y are the same. We can subtract the 2 equations to eliminate y.

Thus,

-78x = -78 ( y has been eliminated)

∴ x=-78/-78 =1.

Put the value of x in any equation to find y.

7x + 5y =2

=> 7(1) + 5y =2

7+5y=2

5y = 2-7

5y = -5

y = -1.

Hope this helps :)

User Vimal Prakash
by
7.8k points