Note the equal sign. What you do to one side, you do to the other.
Also, remember to do the opposite of PEMDAS.
First, subtract 6 from both sides
-2x + 6 (-6) = -20 (-6)
-2x = -26
Next, isolate the x. Divide -2 from both sides
(-2x)/-2 = (-26)/-2
x = -26/-2
x = 13
13, or (B) is your answer
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<em>~Rise Above the Ordinary, Senpai</em>
Tanh x = 12/13
1) Calculate cosh x:
cosh² x = 1/(1-tanh² x) →→ 1/[1-(12/13)²] = 1/(1-144/169) = 1/[(169-144)169]
cosh²x = 169/25 and cosh x = + or - 13/5
2) Calculate sinh x
sinh x/cosh x = tanh x →→sinh x = (cosh x)(tanh x)
sinh x = + or - (13/5)(12/13) →→sinh x= + or - 12/5
From here onward you can calculate easily coth x, sech x, csch x
Answer:
81 is the best answer for this
