Question

X + Y - 4 equal to zero 4 x minus y equal to zero

Answer 1

X+Y=4( 1st equation)
4X-Y=0
4X=Y(2nd equation)
put the value of Y in equation 1st
X+Y=4
X+4X=4
5X=4
X=4/5
put the value of X in equation 1st
Y=16/5

Answer 2

see your answer is in attachment....
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