Question

1.
-0,09+4х^2=0
2.
(x+2)^2-49
(x-10)^2-25y^2

Answer 1

1)

$- 0.09 + 4 {x}^{2} = 0 \\ ({2x})^{2} - {0.3}^{2} = 0 \\ (2x - 0.3)(2x + 0.3) = 0 \\ x = ± \frac{3}{20} = ±0.15$

2)

${(x + 2)}^{2} - 49 = {(x + 2)}^{2} - {7}^{2} = (x + 2 - 7)(x + 2 + 7) = (x - 5)(x + 9)$

3)

${(x - 10)}^{2} - 25 {y}^{2} = {(x - 10)}^{2} - {(5y)}^{2} = (x - 10 - 5y)(x - 10 + 5y)$