Answer:
x=35
Step-by-step explanation:
The sum of angles in a triangle is equal to 180. In the triangle given, we have to add all the angles to find x.
So,
[tex]3x+x+40=180[/tex]
to find x, we must isolate it:
combine common terms:
[tex]4x+40=180[/tex]
subtract the 40 to both sides:
[tex]4x+40-40=180-40[/tex]
divide by three to isolate the variable:
[tex]4x/4=140/4[/tex]
and the resulting would be our x:
[tex]x=35[/tex]
to check if our answers make sense, substitute.
[tex]3(35)+35+40=180[/tex]
solve:
[tex]180=180[/tex]
that's it! hope it helps :)
