Question

a) 6x²-3x=0
B) 25x²=1
C) 4x²+7x-2=0
D) 4x2+20x+25=0
E) 3x²+2x+1=0​

Answer 1

$a)3x(2x - 1) = 0 \\ 3x = 0 \\ 2x - 1 = 0 \\ \\ x = 0 \\ 2x = 1 \\ x = \frac{1}{2} = 0.5$

$b){x}^{2} = \frac{1}{25} \\ x = \sqrt{ \frac{1}{25} } = + - \frac{1}{5} \\ x1 = \frac{1}{5} = 0.2 \\ x2 = - \frac{1}{5} = - 0.2$

$c)4 {x}^{2} + 7x - 2 = 0 \\ dis = 49 + 32 = 81 \\ x1 = \frac{ - 7 + 9}{2 \times 4} = \frac{2}{8} = \frac{1}{4} = 0.25 \\ x2 = \frac{ - 7 - 9}{2 \times 4} = \frac{ - 16}{8} = - 2$

$d)4 {x}^{2} + 20x + 25 = 0 \\ dis = 400 - 400 = 0 \\ x = \frac{ - b}{2a} = \frac{ - 20}{2 \times 4} = - \frac{5}{2} = - 2.5$

$e)3 {x}^{2} + 2x + 1 = 0 \\ dis = 4 - 12 = - 8 \\ dis < 0 \: net \: korney$