10 because the number in the ones place is less than 5 which means u would go down to 10
Answer:
Step-by-step explanation:
A+B+C = 180°
A ≤ B ≤ C
B = A+9
C = 3A+26
A+B+C = A + (A+9) + (3A+26) = 5A + 35° = 180°
5A = 145°
A = 29°
B = A+9 = 38°
C = 3A+26 = 113°
So you make your equation 4x+20+40=180.
Add like terms and get 4x+60=180.
Subtract 60 from both sides, get 4x=120.
Divide boths sides by 4, get your answer of x=30.
Hope this helps