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1 vote

m + 1 = √(4m + 49)


User Dominic P
by
5.4k points

1 Answer

4 votes

First note that if
m is real-valued, then
√(4m+49) only exists if
4m+49\ge0, or
m\ge-\frac{49}4=-12.25.

Square both sides to get


(m+1)^2=(√(4m+49))^2\implies m^2+2m+1=4m+49\implies m^2-2m-48=0

This is easily factorized:


m^2-2m-48=(m-8)(m+6)\implies m=8\text{ or }m=-6

Both of these solutions are larger than
-\frac{49}4, so they are both valid solutions.

User Peter Flom
by
5.6k points