Add: the following

Question

5x square - 1/4x + 2/3y, 2/5x sqaure + 1/3x + 2/3y and -x square + 1/2x-y?

Answer 1

The equations are   5x² -(1/4) x + (2/3)y          ---------------  (1)

                             (2/5)x² + (1/3)x + (2/3)y   ---------------  (2)

                             -x² + (1/2)x -y                  ---------------- (3)

Add the equations (1) and (2)

     5 x²  - (1/4) x + (2/3)y 

 (2/5)x² + (1/3) x + (2/3)y 

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(27/5)x² + (1/12) x + (4/3)y   --------------------------(4) 

Now add the equations (3) and (4)

        -x² + (1/2) x     - y 

(27/5)x² + (1/12) x + (4/3)y

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(22/5)x² + (7/12) x + (1/3)y

So the sum of given equations is (22/5)x² + (7/12) x + (1/3)y .