Question

x(x-3) -2 (x-3) = 3 ??????

Answer 1

x(x - 3) - 2(x - 3) = 3
x² - 3x - 2x + 6 = 3
x² - 5x + 6 - 3 = 0
x² - 5x + 3 = 0

ou:
(x - 2).(x - 3) = 3
x² - 3x - 2x + 6 - 3 = 0
x² - 5x + 3 = 0

a = 1; b = - 5; c = 3

Δ = b² - 4ac
Δ = (-5)² - 4.1.3
Δ = 25 - 12
Δ = 13

x = - b +/- √Δ = - (- 5) +/- √13        
          2a                2.1

R.: 
x = 5 + √13
           2

x = 5 - √13
          2