Solve the equation using the method of completing the square. 2x^2 + 16 - 8 = 0

x=-4+-2 to the square root 5

Step-by-step explanation:1) Move the "non X" term to the right:

2x^2+16x-8=0 becomes

2x^2 +16x = +8

2) Divide the equation by the coefficient of X² which in this case is 2

x^2 + 8x = 4

3) Now here's the "completing the square" stage in which we:

    • take the coefficient of X  (which is 8)

    • divide it by 2  [8 / 2 = 4]

    • square that number  [4^2 = 16]

    • then add it to both sides of the equation.

x^2 + 8x  + 16 = 20

Take the square root of both sides of the equation:

x + 4 = sq root (20)

x = sq root (20) -4

x1 = 4.472135955 -4

x1 = .472135955

x2 = -4.472135955 -4

x2 = -8.472135955

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.