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=
`(-7+/- √(49+256) )/(16)`
x=
`(-7+/- √(305) )/(16)`

x=
`(-7+ √(305) )/(16)` or x=
`(-7- √(305) )/(16)`

aprox
x=-1.52902 or 0.654016