Solve x2 – 8x + 41 = 0 for x.

x=-4 (-+)square root of 37i
x = –4 ± 5i

x=4(-+) square root of 37i
x = 4 ± 5i

The equation is quadratic equation that requires finding discriminant

Since discriminant is negative, this equation has two complex roots. Note that where is imaginary unit. Then

Now the complex roots are

correct choice is D.

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form

the answer is 40.

proof: