B squared plus 20b equals -80?

Answer 1

-60

Answer 2

B squared plus 20b equals -80?

Use quadratic equation. I will go thru this one step at a time.

b^2 + 20b = -80 ..add +80 to both sides

b^2 + 20b +80 = 0

General quadratic equation

ax^2 +bx + c = 0

x = [-b ± (b^2 - 4*a*c)^0.5] ÷ 2*a

In your equation

a =1

b = 20

c = 80

Substituting these values into the general equation:

x = [-20 ± (20^2 - 4*1*80)^0.5] ÷ 2*1

x = [-20 ± (400 - 320)^0.5] ÷ 2

x = [-20 ± 80^0.5] ÷ 2

X1 = [-20 + 80^0.5] ÷ 2

X2 = [-20 - 80^0.5] ÷ 2

I got X1 = -5.528 and X2 = -14.47

Or go to a quadratic equation solver web site such as

http://www.math.com/students/calculators/source/quadratic.htm