Question

como faz essa conta (x-3).(2x-10)=0​

Answer 1

Resposta:

$x*2x = 2x^{2} \\x*-10 = -10x\\\\-3*2x = -6x\\-3*-10=30\\\\2x^{2} -10x-6x+30=0\\2x^{2} -16x+30=0\\\\D=Delta\\a=2\\b=-16\\c=30\\\\D=-16^{2} -4*2*30\\D=256-240\\D=\sqrt{16} \\\\x=\frac{-(-16)\sqrt{16} }{2*2} \\\\x1=16+4/4=5\\x2=16-4/4=3$