number is 'n'
square of a number means n^2
added to means plus or +
number trippled is 3n
result means equals or =
108 is 108
n^2+3n=108
minus 108 from both sides
n^2+3n-108=0
if want quadratic formula
in form
ax^2+bx+c=0
x=\(\frac{-b+/- \sqrt{b^2-4ac} }{2a}\)
a=1
b=3
c=-108
x=\(\frac{-3+/- \sqrt{3^2-4(1)(-108)} }{2(1)}\)
x=\(\frac{-3+/- \sqrt{9+432} }{2}\)
x=\(\frac{-3+/- \sqrt{441} }{2}\)
x=\(\frac{-3+/- 21 }{2}\)
x=\(\frac{-3+21 }{2}\) or x=\(\frac{-3- 21}{2}\)
x=\(\frac{18 }{2}\) or x=\(\frac{-24}{2}\)
x=9 or -12
the number is either 9 or -12
