The second angle of a triangle is double the first(110). The third angle is 40 less than
the first(15). Find the first angle.
Choose the correct choice from the following options:
A) 35
B) 45
C) 55
D) 65
E) 75
First x With nothing given about the firstwemake that x   Second 2x The second is double the first,   Third x−40 The third is 40 less than the first   F +S +T =180 All three angles add to 180   (x)+(2x)+(x−40)=180 Replace F , S, and T with the labeled values.   x+2x+x−40=180 Here the parenthesis are not needed.   4x−40=180 55ombine like terms, x+2x+x   +40 +40 Add 40 to both sides   4x=220 The variable ismultiplied by 4   4 4 Divide both sides by 4   x=55 Our solution for x   First 55 Replace xwith 55 in the original list of angles   Second 2(55)=110 Our angles are 55, 110, and 15   Third (55)−40=15   correct answer 55
<result>C</result>
The second angle of a triangle is double the first(110). The third angle is 40 less than
the first(15). Find the first angle.