Question

solve the equation by completing the square. Round to the nearest hundredth if necessary.
x^2 + 10x = 18
–11.56, 1.56
11.56, 1.56
–11.56, –1.56
11.56, –1.56

Answer 1

use (b/2)^2 to get your new value of C, and add to both sides. (25 in this case)

x^2+10x+25=43

change to:

(x+5)^2=43

take square roots

\[x+5=\pm \sqrt{43}\]
subtract the 5.
\[x=-5\pm \sqrt{43}\]

Answer 2

is it b?

Answer 3

nope