10x²+5x=0

25-100x²=0

2x²-14=0

2x²-8=0

4x²-12=0

x²-10x=0

4x²+20x=0

2x²+x=0

3x²-27=0

4x²+20x=0

5X (2X + 1) = 0 - - > X = - 0.5

25 - 100X^2 = 25 * (1 - 4X^2) = 25 * (1 - 2X) (1+2X) - - > X 1 = + 0.5 X2 = - 0.5

25X^2 - 14 = 0; 25X^2 = 14; X^2 = 0.56 - - > X = V 0.56

2X^2 - 8 = 0; 2X^2 = 8; X^2 = 4; X1 = 2; X2 = - 2

4X^2 - 12=0; 4X^2 = 12; X^2 = 3; X = V 3

x^2 - 10X = 0; X (X - 10) = 0--> X = 10

4X^2 + 20X = 0; 4X (X + 5) = 0--> X = - 5

2X^2 + X = 0; X (X + 1) = 0 - - > X = - 1

3X^2 - 27 = 0; 3 (X^2 - 9) = 0; 3 (X-3) (X+3) = 0--> X1 = 3; X2 = - 3

4X^2 + 20X = 0; 4X (X + 5) = 0; X = - 5