SOLUTION: how do you solve tan squaredx +3tanx-10=0

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Question 869107: how do you solve tan squaredx +3tanx-10=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use a substitution,
u=tan%28x%29
u%5E2%2B3u-10=0
%28u%2B5%29%28u-2%29=0
Two "u" solutions:
u%2B5=0
u=-5
tan%28x%29=-5
x=281.3 and x=101.3
and
u-2=0
u=2
tan%28x%29=2
x=63.4 and x=243.4