5x-(8x+2) = 5x-26
-8x-2=-26
-8x=-24
x=3

2)

1/3+9/x = 5/6 /18x

6x+18*9 = 15x

2x+54 = 5x

54 = 3x

18 = x

3)

z^2+2z-15 = 0

(z+5)(z-3) = 0

z=-5 and z=3

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