2(X+2)^2（2次方）-72/49=0
（x+2)^2=36/49
x+2=+-6/7
x1=-20/7 x2=8/7
l2x-y-7l+根号x+2y-39=0
2x-y-7=0
x+2y-39=0
x=53/5
y=71/5
3x+2y=159/5+142/5=301/5
3x+2y的平方根为+-根号1505/5
2(X+2)^2（2次方）-72/49=0
（x+2)^2=36/49
x+2=+-6/7
x1=-20/7 x2=8/7
l2x-y-7l+根号x+2y-39=0
2x-y-7=0
x+2y-39=0
x=53/5
y=71/5
3x+2y=159/5+142/5=301/5
3x+2y的平方根为+-根号1505/5