Hola !
<img src="https://tex.z-dn.net/?f=%20%5Csqrt%7Bx%7D%20%2B%20%5Cfrac%7B4%7D%7B%20%5Csqrt%7Bx%7D%20%7D%20%3D4" />
<img src="https://tex.z-dn.net/?f=%20%5Csqrt%7Bx%7D%20.%20%5Csqrt%7Bx%7D%20%2B4%3D4%20%5Csqrt%7Bx%7D%20" />
<img src="https://tex.z-dn.net/?f=%20%5Csqrt%7B%20x%5E%7B2%7D%20%7D%20%2B4%3D4%20%5Csqrt%7Bx%7D%20" />
<img src="https://tex.z-dn.net/?f=x%2B4%3D4%20%5Csqrt%7Bx%7D%20" />
<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7Bx%2B4%7D%7B4%7D%20%3D%20%5Csqrt%7Bx%7D%20" />
<img src="https://tex.z-dn.net/?f=%20%20%28%5Cfrac%7Bx-4%7D%7B4%7D%20%29%5E%7B2%7D%20%3Dx" />
<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7B%28x%2B4%29%5E%7B2%7D%20%7D%7B4%5E%7B2%7D%20%7D%20%3Dx" />
Binomio al cuadrado : (a + b)² = a² + 2ab + b²
(x - 4)² = x² + 2(x)(4) + 4² x² + 8x + 16
Remplazamos :
<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7B%20x%5E%7B2%7D%20%2B8x%2B16%7D%7B16%7D%20%3Dx" />
<img src="https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20%2B8x%2B16%3D16x" />
<img src="https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20%2B8x-16x%2B16" />
[img = 10]
Respuesta : La ecuación cuadrática es [img = 11]
Suerte y saludos !