1) 2x (5x-7) = 2x^-5

2) (x+4) ^ = 4x^+5

3) (x-5) ^ = 3x^-x+14

4) 9x (4x-1) = 3x-1

1) 2x (5x-7) = 2x^-5

10x²-14x-2x²+5=0

8x²-14x+5=0

D=b²-4ac=14²-4·8·5=196-160=36, 2 корня

x1=14+√36/16=14+6/16=20/16

x2=14-6/16=8/16=1/2

2) (x+4) ^ = 4x^+5

x²+8x+16-4x²-5=0

-3x²+8x+11=0 |· (-1)

3x²-8x-11=0

D=b²-4ac = (-8) ²-4·3· (-11) = 64+132=196, 2 корня

x1=8+√196/6=8+14/6=22/6=11/3

x2=8-14/6=-6/6=-1

3) (x-5) ^ = 3x^-x+14

x²-10x+5²=3x²-x+14

x²-10x+25-3x²+x-14=0

-2x²-9x+11=0 |· (-1)

2x²+9x-11=0

D=b²-4ac=9²-4·2· (-11) = 81+88=169, 2 корня

x1=-9+√169/4=-9+13/4=4/4=1

x2=-9-13/4=-22/4=-5.5

4) 9x (4x-1) = 3x-1

36x²-9x-3x+1=0

36x²-12x+1=0

D=b²-4ac = (-12) ²-4·36·1=144-144=0? 1 корень

x=12+0/36=12/36=1/3