How do you solve t^2 + 13t + 42 = 0 using the quadratic formula?

1 Answer
Apr 26, 2016

The solutions for the equation are:
color(green)( t =-6, color(green)( t =-7

Explanation:

t^2 + 13t + 42 = 0

The equation is of the form color(blue)(at^2+bt+c=0 where:

a=1, b= 13, c=42

The Discriminant is given by:

color(blue)(Delta=b^2-4*a*c

= (13)^2-(4* 1 * 42)

= 169 - 168 = 1

The solutions are found using the formula
color(blue)(t=(-b+-sqrtDelta)/(2*a)

t = ((-13)+-sqrt(1))/(2*1) = (-13+- 1)/2

t = (-13+ 1)/2 = -12 /2 = -6

t = (-13- 1)/2 = -14/2 = -7

The solutions are:

  • color(green)( t =-6
  • color(green)( t =-7