Question 1007374
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what is the length of AB in a triangle equation is x+4+x+x+5=21 then find AB x+4=
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If the original equation is x+4+x+x+5=21, then it is equivalent to

3x + 9 = 21,

3x = 21 - 9,

3x = 12,

and has the solution x = {{{12/3}}} = 4.

Then AB = x + 4 = 4 + 4 = 8.
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