solve by completing square- x*+10x+13=0?

x^2 + 10x + 13 = 0
x^2 + 5x + 5x + 25 - 12 = 0
(x^2 + 5x) + (5x + 25) - 12 = 0
x(x + 5) + 5(x + 5) = 12
(x + 5)(x + 5) = 12
(x + 5)^2 = 12
x + 5 = ±√12
x + 5 ≈ ±3.46

x + 5 ≈ 3.46
x ≈ 3.46 - 5
x ≈ -1.54

x + 5 ≈ -3.46
x ≈ -3.46 - 5
x ≈ -8.46

∴ x ≈ -8.46 , -1.54

x^2 + 10x = -13 now divide 10 through 2 and sq. that answer, you should get 10/2=5 5^2=25 x^2 + 10x +25 = -13 + 25 x^2 + 10x +25 = 12 (x+5)^2=12 squareroot(x+5)^2 = squareroot12 x+5= (+-)12 x=-5 +12 x=7******** or x=-5-12 x=-17********** sorry, i do not comprehend a thanks to make all the shortcut symbols

You have inserted a sign "-" and you have x* whatever that may mean.
This is confusing.

Will GUESS at :-
x² + 10x + 13 = 0
(x² + 10x + 25) - 25 + 13 = 0
(x + 5)² = 12
x + 5 = ±√12
x + 5 = ± 2√3
x = - 5 ± 2√3

First, move the 13 over to the right side:

x^2+10x= -13

Take half of the number on the "x" term (10/2=5), square it (5^2=25), and add it to both sides.

x^2 + 10x + 25 = 12

Factor the left side.

(x+5)^2=12

Take the square root of both sides.

x+5 = +/- sqrt(12)

Square root of 12 can be simplified.

x+5 = +/- 2sqrt(3)

Solve for x to get your two solutions.

x = -5 + 2sqrt(3), -5 - 2sqrt(3)

Hope this helps. :)

-[X^2-10X-13]=0

-[(X-5)^2 -5^2 +13]=0

-[(X-5)^2 -25 +13]=0

-(X-5)^2 +12 =0

-(x-5)^2= -12
(x-5)^2= 12
(x-5)=square root of 12

x=( square root of 12) +5

^ means to the power of

2 to the second power+10(-2)+13=0