1. 2-9x^2=0

2. - 15-2x^2=-11x

3. - 0,36-x^2=0

4. 16x+64=-x^2

5. 13x+3x^2=-14

6. 7x^2-3x=0

7. 5=2x-x^2

8. 16+x^2=8x

9. 1-4x^2+3x=0

10. - 12x+4=-9x^2

11. 10x^2-2=x

1) 2-9x^2=0

9x^2=2

x^2=2/9

x1=sqr2/3

x2=-sqr2/3

2) - 15-2x^2=-11x

-2x^2+11x-15=0

d=121-4 (-2) (-15) = 121-120=1

x1 = (-11-1) / 2=-6

x2 = (-11+1) / 2=-5

3) - 0.36-x^2=0

(-1) x^2=0,36

x^2=-0,36 такого быть не может.

4) 16x+64=-x^2

x^2+16x+64=0

d=256-4*1*64=256-256=0

x=-16/2=-8

5) 13x+3x^2=-14

3x^2+13x+14=0

d=169-4*3*14=169-168=1

x1 = (-13-1) / 6=-14/6=-7/3

x2 = (-13+1) / 6=-12/6=-2

6) 7x^2-3x=0

x (7x-3) = 0

x1=0

x2=7x-3=0

x2=3/7

7) 5=2x-x^2

x^2-2x+5=0

d=4-4*5=4-20 d<0 корней нет

8) 16+x^2=8x

x^2-8x+16=0

d=64-4*16=64-64=0

x=8/2=4

9) 1-4x^2+3x=0

-4x^2+3x+1=0

d=9-4 * (-4) = 9+16=25=5^2

x1 = (-3+5) / (-8) = - 1/4

x2 = (-3-5) / (-8) = 1

10) - 12x+4=-9x^2

9x^2-12x+4=0

d=144-4*9*4=144-144=0

x=12/18=4/6=2/3

11) 10x^2-2=x

10x^2-x-2=0

d=1-4*10 * (-2) = 1+80=81=9^2

x1 = (1-9) / 20=-8/20=-4/10=-2/5

x2 = (1+9) / 20=10/20=1/2