Answer:
569
Hope I helped :D
Step-by-step explanation:
I think the equation would be 5m+n=17 I might be wrong so sorry but that is what I think it is
The measurement of angle a plus 120 must equal to 180 ( as angles on a straight line must equal to 180)
So measurement of angle a is 60 degrees
Measurement of angle b plus 60 plus 60 must equal to 180
So measurement of angle b is 60
Total people x,
then, 3.5x + 5.5x + 6 = 51
simplify, 9x +6 = 51
subtract 6 on both sides, 9x= 45
divide by 9 on both sides, x= 5
therefore, total 5 people in the family.
