bjr
46 x 45 + 45 x 54 = 45 (46 + 54) = 45 x 100 = 4500
donc 34x17 + 34x3 = 37x(17+3) = 37x20 = 740
6x + 6y = 6 (x+y)
yx + 6yx = yx (1+6) = 7yx
y*9y - 6*9 = 9(y² - 6)
6a + a*a = a(6+a)
4x+8 = 4*x + 4*2 = 4(x+2)
15x + 35x²= 5x*3 + 5x*7x = 5x(... tu finis)