make equal to zero
add7 both sides
8m^2+7m-8=0
quadratic fomrula
if you have
ax^2+bx+c=0
x=\(\frac{-b+/- \sqrt{b^{2}-4ac} }{2a}\)
8m^2+7m-8=0
a=8
b=7
c=-8
x=\(\frac{-7+/- \sqrt{7^{2}-4(8)(-8)} }{2(8)}\)
x=\(\frac{-7+/- \sqrt{49+256} }{16}\)
x=\(\frac{-7+/- \sqrt{305} }{16}\)
x=\(\frac{-7+ \sqrt{305} }{16}\) or x=\(\frac{-7- \sqrt{305} }{16}\)
aprox
x=-1.52902 or 0.654016
