Question

Solve x2 - 8x = 20 by completing the square. Which is the solution set of the equation

Answer 1

Answer:

x = 10 or x = -2

Step-by-step explanation:

${x}^{2} - 8x = 20 \\ {x}^{2} - 2 \times x \times 4 + {4}^{2} - {4}^{2} = 20 \\ {x}^{2} - 8x + 16 - 16 = 20 \\ {x}^{2} - 8x + 16 = 20 + 16 \\ {(x - 4)}^{2} = 36 \\ |x - 4| = \sqrt{36} \\ |x - 4| = 6 \\ x - 4 = + - 6 \\ x = 4 + - 6 \\ \\ x = 4 + 6 = 10 \\ or \\ x = 4 - 6 = - 2$

Answer 2

Answer: D

Step-by-step explanation:

basically how i remember to do this is asking myself what multiples to 20 and then what adds up to -8