Question

сейчас надо, срочно​

Answer 1

1)

$\displaystyle \tt 5x^2-14x-3=0\\\displaystyle \tt D=(-14)^2-4\cdot5\cdot(-3)=196+60=256\\\displaystyle \tt \sqrt{D}=\sqrt{256}=16\\\\ \displaystyle \tt \bold{x_1}=\frac{14+16}{2\cdot5}=\frac{30}{10}=3\\\\ \displaystyle \tt \bold{x_2}=\frac{14-16}{2\cdot5}=\frac{-2}{10}=-\frac{1}{5}=-0,2$

2)

$\displaystyle \tt 3x^2+24x=0\\\displaystyle \tt 3x(x+8)=0\\\\ \displaystyle \tt 3x=0\\\displaystyle \tt \bold{x_1=0}\\\\ \displaystyle \tt x+8=0\\\displaystyle \tt \bold{x_2=-8}$

3)

$\displaystyle \tt 2x^2-32=0\\\displaystyle \tt 2(x^2-16)=0\\\\ \displaystyle \tt x^2-16=0\\\displaystyle \tt x^2=16\\\displaystyle \tt x=\sqrt{16}\\\displaystyle \tt \bold{x_1}=4\\\displaystyle \tt x=-\sqrt{16}\\\displaystyle \tt \bold{x_2=-4}$