solve the equation by completing the square. Round to the nearest hundredth if necessary.
x^2 + 10x = 18 (1 point)
–11.56, 1.56
11.56, 1.56
–11.56, –1.56
11.56, –1.56

Question

solve the equation by completing the square. Round to the nearest hundredth if necessary.
x^2 + 10x = 18  (1 point)
–11.56, 1.56
11.56, 1.56
–11.56, –1.56
11.56, –1.56

campbell_st · Answer

add (b/2)^2  to both sides  (10/2)^2 = 25

x^2 + 10x + 25 = 43

(x + 5)^2 = 43

then taking thesquare root of both sides
$$x + 5 = \pm \sqrt{43}$$
then

$$x = -5 \pm \sqrt{43}$$

you need to evaluate the last part correct to 2 decimal places.