Question

If 10x +5y =20 and 5x + 10y =40 then what is the value of x +y =?​

Answer 1

hence x=0 and y = 4

this x+y=4

Answer 2

Answer:

Step-by-step explanation:

10x+5y=20     eq1

5x+10y=40     eq2

multiply  eq by 2

10x+5y=20

10x+20y=80

-       -        -           sign will be changed

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    -15y = -60  (cancel -  sign and )

y=60/15=4

put y=4 in any eq and

x=0

x+y=4