How do you solve #m^2 -5m - 14=0# using the quadratic formula?

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Answer 1 · 2017-05-24T23:43:39

#x=-2,7#

Solve:

#m^2-5m-14=0#,

This is a quadratic equation in standard form: #ax^2+bx+c=0,# where #a=1#, #b=-5#, and #c=-14#.

#x=(-b+-sqrt(b^2-4ac))/(2a)#

Insert the given values into the formula.

#x=(-(-5)+-sqrt((-5)^2-4*1*-14))/(2*1)#

Simplify.

#x=(5+-sqrt(25+56))/2#

Simplify.

#x=(5+-sqrt(81))/2#

Simplify.

#x=(5+9)/2,##x=(5-9)/2#

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Solutions for #x#.

#x=(5+9)/2#

#x=14/2#

#x=7#

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#x=(5-9)/2#

#x=-4/2#

#x=-2#

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#x=-2,7#