Answer:
18 ducks
Step-by-step explanation:
add the parts of the ratio 7 + 6 = 13
divide the total by 13 to find one part of the ratio
= 3 ← 1 part of the ratio
7 parts = 7 × 3 = 21 ← number of swans
6 parts = 6 × 3 = 18 ← number of ducks
B
|x – 10| – 4 = 2x
x - 10 - 4 = 2x
x - 14 = 2x
x - 2x = 14
-x = 14
x = -14