Question

X^2+4x=7 using the quadratic formula?

Answer 1

when you have
ax^2+bx+c=0
x=
`\frac{-b+/- \sqrt{b^(2)-4ac} }{2a}`


1x^2+4x=7
minus 7
1x^2+4x-7=0
a=1
b=4
c=-7
sub

x=
`\frac{-4+/- \sqrt{4^(2)-4(1)(-7)} }{2(1)}`
x=
`(-4+/- √(16+28) )/(2)`
x=
`(-4+/- √(44) )/(2)`
x=
`(-4+/- 2√(11) )/(2)`
x=
`-2+/- √(11)`

x=
`-2+ √(11)` or
`-2- √(11)`