Question

Ajudinha por gentileza!! :)
2.Resolva as equações do 2°grau.
A)2x²-15x=0
B)3x²=27
C)8x²-2x=0​

Answer 1

a) $2x^2-15x=0$

$x^2-\frac{15}{2} x=0$

$x(x-\frac{15}{2} )=0$

$x^1=0\\x^2=\frac{15}{2}=7,5$

b) $3x^2=27$

$x^2=\frac{27}{3}$

$x^2=9$

$x=\sqrt{9}$

$x= \pm 3$

$x^1=-3\\x^2=3$

c) $8x^2-2x=0$

$2x \times (4x-1)=0$

$x \times (4x - 1) =0$

$x=0\\4x-1=0$

$x^1=0\\x^2=\frac{1}{4}=0,25$