С 385 по 394 плииииз.... .....

385. $10x^2+5x=0 \\5x(2x+1)=0 \\x(2x+1)=0 \\ x=0; 2x+1=0 \\ x=0; 2x=-1 \\ x=0; x=-\frac{1}{2}$
386. $12x^2+3x=0 \\ 3x(4x+1)=0 \\ x(4x+1)=0 \\ x=0; 4x+1=0 \\ x=0; 4x=-1 \\ x=0; x=-\frac{1}{4}$
387. $25-100x^2=0 \\ -25(2x-1)(2x+1)=0 \\ (2x-1)(2x+1)=0 \\ 2x=1; 2x=-1 \\ x=\frac{1}{2}; x=-\frac{1}{2}$
388. $4-36x^2=0 \\ -4(3x-1)(3x+1)=0 \\ (3x-1)(3x+1)=0 \\ 3x-1=0; 3x+1=0 \\ 3x=1; 3x=-1 \\ x=\frac{1}{3}; x=-\frac{1}{3}$
389. $2x^2-14=0 \\ 2x^2=14 \\ x^2=7 \\ x=\sqrt{7}; x=-\sqrt{7}$
390. $3x^2-6=0 \\3x^2=6 \\ x^2=2 \\ x=\sqrt{2}; x=-\sqrt{2}$
391. $2x^2-8=0 \\ 2(x-2)x+2)=0 \\ (x-2)(x+2)=0 \\ x-2=0; x+2=0 \\ x=2; x = -2$
392. $3x^2-75=0 \\ 3 (x-5)(x+5)=0 \\ (x-5)(x+5)=0 \\ x-5=0; x+5=0 \\ x=5; x=-5$
393. $4x^2-12=0 \\ 4x^2=12 \\ x^2=3 \\ x=\sqrt{3}; x=-\sqrt{3}$
394. $3x^2-15=0 \\ 3x^2=15 \\ x^2=5 \\ x =\sqrt{5}; x=-\sqrt{5}$