SOLUTION: Hi i need help solving these equations: the square root of (2r squared - 121)= r and : 4+ square root of (m-2)=m

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Question 226867: Hi i need help solving these equations: the square root of (2r squared - 121)= r
and : 4+ square root of (m-2)=m
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%282r%5E2+-+121%29 = r
Square both sides and you have
2r^2 - 121 = r^2
2r^2 - r^2 = + 121
r^2 = 121
r = sqrt%28121%29
r = +11 is the valid solution
;
;
4+%2B+sqrt%28m-2%29 = m
sqrt%28m-2%29 = m - 4
Square both sides
m - 2 = (m-4)^2
m - 2 = m^2 - 8m + 16
0 = m^2 - 8m - m + 16 + 2
A quadratic equation
m^2 - 9m + 18
Factors to
(m-6)(m-3) = 0
m = 6
and
m = 3
:
You check both solutions in original equation, only one is valid