Porfas ayúdenme ni tengo quien me ayude las 6?

<img src="https://tex.z-dn.net/?f=%204x%5E%7B2%7D%20%3D%201" />

4x ^ {2} - 1 = 0

(2x + 1)(2x - 1) = 0

2x + 1 = 0 2x - 1 = 0

2x = - 1 2x = 1

<img src="https://tex.z-dn.net/?f=x%20%3D%20-%20%5Cfrac%7B1%7D%7B2%7D%20" /> <img src="https://tex.z-dn.net/?f=x%20%3D%20%20%5Cfrac%7B1%7D%7B2%7D%20" />

<img src="https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20-x%20-56%20%3D%200%0A" />

x - 8x + 7 - 8x + 7x = - x

(x - 8)(x + 7) = 0

x - 8 = 0 x + 7 = 0x = 8 x = - 7

CS = ( - 7 ; 8)

<img src="https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20%2B%209x%20%3D%200%20" />

x(x + 9) = 0

x = 0 x + 9 = 0 x = - 9

CS = ( - 9 ; 0).