Question

find the values of X and Y in 3x-5y = 8 and 7x+y= 6

Answer 1

3x-5y =8 (1st equation)
7x+y = 6 (2nd equation)
in 2nd equation
y = 6-7x
substitute this value of y in 1st equation
3x-5(6-7x) = 8
3x-30+35x= 8
38x=38
x=1
now we have x=1 so substitute this value of x in any of the equation ,
y= 6-7(1) = 6-7 = -1
hope this helps

Answer 2

3x-5y=8................eq1
7x+y=6.................eq2

multiplying equation 1 with 7
=21x-35y=56

multiplying equationn 2 with 3 
=21x+3y=18

[eq1-eq2]

=>21x-35y -21x-3y=56-18
=>-38y=38
=>y=[-1]

substituting y = -1 in eq 1
=>3x-5y=8
=>3x-5[-1]=8
=>3x+5=8
=>3x=3
x=1


therefore x=1 and y=-1