For what positive value of m will the following equation be true if n=5?(m+n)2+(m−n)2+m2+n2=318.
(m + 5)^2 + (m - 5)^2 + m^2 + 5^2 = 318 simplify
m^2 +10m + 25 + m^2 - 10m + 25 + m^2 + 25 = 318
3m^2 + 75 = 318 subtract 75 from both sides
3m^2 = 243 divide both sides by 3
m^2 = 81 take the positive square root
m = √81
m = 9
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+209 
