If using the method of completing the square to solve the quadratic equation x 2 − 10 x − 20 = 0 x 2 −10x−20=0, which number would have to be added to "complete the square"?

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116

so the rectangle is 80cm (area)

now to find the area of a triangle.

base times height.

4 times 8.

your answer is 96cm.

hope this .

just a girl thing, i think im cute when im not lol

d. 5.43x1012 h.5.43e12