n = a number
2n = twice a number
2n - 7 = seven less than twice a number
Answer:
Sydney is 52 years old, and Tristan is 30.
Step-by-step explanation:
Represent Tristan's age by t and Sydney's by s.
Then s - 8 = 2(t - 8), and t = s - 22
Substituting s - 22 in the first equation, we get:
s - 8 = 2(s - 22 - 8), or
s - 8 = 2s - 60
Solving for s: -2s + s = -60 + 8, or -s = -52.
Sydney is 52 years old, and Tristan is 30.
10 x 2 = 20
5 x 16 = 80
80 + 20 = 100
10=2 points questions and 16 =5 points questions