Answer:
Huilan is 11. Thomas is 20
Step-by-step explanation:
X+(x+9)=31
2x-9=31
2x=22
X=11
Answer:
Thomas is 20 years old.
Step-by-step explanation:
We can represent Huilan and Thomas's ages with variables. We will make Thomas's age x and Huilan's age y.
To solve this problem, we need to setup a system of equations. We know that their ages add up to be 31 years, so we can simply set the sum of x and y equal to 31. Secondly, we know that Huilan is 9 years younger than Thomas, so we subtract 9 from x and set it equal to y (Huilan's age).
x + y = 31
x - 9 = y
x + (x - 9) = 31
2x - 9 = 31
2x = 40
x = 20
20 + y = 31
y = 11
Therefore, Huilan is 11 years old. We can also determine because we solved for x that Thomas is 20 years old.
