Question

resolva essa equação 3x(x+3)=30

Answer 1

3x(x+3)=30 3x^2 + 9x -30=0 Δ= 81+ 360 Δ= 441 x = -9 +ou - √441/2.3 x = -9 + ou - √441/6∴ x'= -9 + 21/6∴ x'= 12/6= 2.∴ x"=-9-21/6= -30/6=-5