Question

if 11 x+13y=7.4 and 13x+11y=7.0 then 10 x+y=7
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Answer 1

Answer:

Answer

13x+11y=70−−−eqn(1)

11x+13y=74−−−eqn(2)

Multiplying eqn(1) with 11

11(13x+11y)=11×70

⟹143x+121y=770−−−eqn(3)

Multiplying eqn(2) with 13

13(11x+13y)=13×74

143x+169y=962−−−eqn(4)

Subtracting eqn(3) from eqn(4) we get,

48y=192 ⟹y=4

Now let us eliminate y.

Multiplying eqn(1) with 13 then we get,

169x+143y=910−−−eqn(5)

Multiplying eqn(2) with 11, we get

121x+143y=814−−−−eqn(6)

Subtracting eqn(6) from eqn(5),we get x=2

So x=2 and y=4 is our solution

hope it helps you!