Answer:
(7.5,4.1)
Explanation:
Given
3x_7y =_40
3x_2y=_4
sol
3x_7y=_40..... equation 1
3x_2y=_4 ..... eq 2
here
eq 2 multi 3 eq 1 multiply 3
9x_21y=_120
9x_6y=_12
_ + = +
__________
0x+ 15y =108
y=108÷15
y=7.5
the y value putting the eq 1
3x_7y=_40
3x_7×7.5=_40
3x_52.5=_40
3x=52.5_40
3x=12.5
x=12.5÷3
x=4.1