Question

What is the solution to the quadratic equation 8m^2+7m-15=-7 ?

Answer 1

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