I don't know how you expand it but the answer is 3x + 25 unless that's expanding.
You would use cross multiplication:
X/2,000 = 3/5
Multiply: 2,000*3= 6,000
Divide: 6,000/5
Answer: 1,200 doctors use brand x
Rounding 2 SF would give you 19
On the third step it adds 8 on both sides. You are suppose to subtract 8 on both sides.
A is 40
B is 50
C is 115
Explanation, A is the same as the opposite, A + B + 90 = 180, and C + 65 = 180
