Solve the following system of equations 3x - 4y = 25 -2x + y = -10

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3x -4y = 25.........(1)

-2x + y = -10...........(2)

We will use the elimination method to solve.

Multiply (2) by 4.

==> -8x + 4y = -40

Now we will add to (1).

==> -5x = -15

Now we will divide by -5.

==> x = 3

Now, from (2) we will rewrite:

y= -10 + 2x

==> y= -10+2*3 = -10+ 6 = -4

==> y= -4

Then, the solution to the system is : x= 3 and y= -4 or the pair (3,-4).

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We have to solve the system of equations

  • 3x - 4y = 25
  • -2x + y = -10

3x - 4y = 25

=> 3x = 25 + 4y

=> x = ( 25 + 4y)/3

substitute in -2x + y = -10

=> -2 ( ( 25 + 4y)/3) + y = -10

=> ( 25 + 4y)/3 - y/2 = 5

=> 2( 25 + 4y) - 3y = 30

=> 50 + 8y - 3y = 30

=> 5y = -20

=> y = -20/ 5

=> y = -4

x = ( 25 + 4y)/3

=> (25 - 16) / 3

=> 9/3

=> 3

Therefore x = 3 and y = -4

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