Logarithm?

1.
(2^2x)(3^3y)=31.4
(x log 2^2)+(y log 3^3)=log 31.4
(5^5x)(7^7y)=36.6
(x log 5^5)+(y log 7^7)=log 36.6
x=-4.592892308
y=2.977668192

2
5(2^x)=3^y
log 5+(x log 2)=y log 3
(x log 2)-(y log 3)=-log 5
x^2+y = 27.5
x1=4.796730793
x2=-5.427660547
y1=4.491373698
y2=-1.95949901

3.
我不知道是打錯了方程或是打少了東西的，所以不能幫你計算。