Verified answer

x^2 + 2x = -10

ADD 1

x^2 +2x +1 = -9

( x+1)^2 = -9

x = 3i - 1 OR - 3i -1 ANSWER

we have the solution of quadratic equation as

x=(-b+/-sqrt.(b^2-4ac))/2a

comparing your equation with ax^2+bx+c=0, we get

a=1, b=2 and c=10

now using the formula we get

x=(-2+/-sqrt.(2^2-4×1×10))/(2×1)

x=(-2+/-sqrt(4-40))/2

x=(-2+/-sqrt(-36))/2

you can see that the number inside square root is negative which means that it gives the complex number i.e. sqrt.(-36) = 6i where i^2=-1 called imaginary number

so x=(-2+/-6i)/2

now using +ve sign

x=-1+3i

and using -ve sign

x=-1-3i

so the solution to your equation is x=-1+3i and -1-3i

Apply the quadratic formula:

x = [-b ± √b^2 - 4ac] / 2a

x = [-2 ± √(2)^2 - 4(1)(10)] / (2)(1)

x = [-2 ± √4 - 40] / 2

x = [-2 ± √-36] / 2

Simplify the radical:

x = [-2 ± 6i] / 2

Simplify the fraction:

x = -1 ± 3i

That is now in its simplest form.

x = [ - b ± √ ( b ² - 4 a c ) ] / 2 a

x = [ - 2 ± √ ( 4 - 40 ) ] / 2

x = [ - 2 ± i √ 36 ] / 2

x = [ - 2 ± 6 i ] / 2

x = - 1 ± 3 i

The answer is always 7