the ratio of the angles of a triangle are 7 14 15 what is the measure of the second largest triangle

Question

i believe I'm supposed to use the proportion 14/36 = x/90 

Answer 1

7x+14x+15x=180 (the sum of the 3 angles of a triangle is 180)

36x=180

x=180/36

x=5

14*5=70

 

14/36=x/180 will do it

cross multiply or simplify first

7/18=x/180

18*x=7*180

18x=1260

x=1260/18

x=70

or...

18*10=180 so 7*10=70