1) 9 (9-5x) ^2+17 (9-5x) + 8=0

2) 8 (10-3x) ^2-5 (10-3x) - 3=0

9-5x = m

9m^2 + 17m + 8 = 0

D = 289 - 72*4 = 1

m1 = (-17 - 1) / 18 = - 1

m2 = (-17 + 1) / 18 = - 8/9

9 - 5x = - 1

x = 2

9 - 5x = - 8/9

x = 89/45

10 - 3x = n

8n^2 - 5n - 3 = 0

D = 25 + 96 = 121

n1 = (5 - 11) / 16 = - 3/8

n2 = (5 + 11) / 16 = 1

10 - 3x = - 3/8

x = 21/24 = 7/8

10 - 3x = 1

x = 3