It is known that the equation m (4x + 5) + n (3x-4) = 17x-2 about X has infinite solutions

It is known that the equation m (4x + 5) + n (3x-4) = 17x-2 about X has infinite solutions

m(4x+5)+n(3x-4)=17x-2
(4m+3n-17)x=4n-5m-2
When 4m + 3n-17 = 4n-5m-2 = 0, it holds no matter when x takes any value
4m+3n-17=0 (1)
4n-5m-2=0 (2)
(1)*5+(2)*4
20m+15n-85+16n-20m-8=0
31n-93=0
n=3
m=(4n-2)/5=2
mn=6