Answer: (Sorry for not wording it correctly I had to reword it)
Step-by-step explanation: Let R be the current age of Rita. Let S be the current age of her son.
Rita is twice as old as her son.
=> R = 2S
In 4 years, R will be 4 times as old as S was 9 years ago
=> R + 4 = 4 (S - 9)
Solve for R, and S:
=> R + 4 = 4 (S - 9)
=> (2S) + 4 = 4(S - 9)
=> 2S + 4 = 4S - 36
=> 2S - 4S = -36 - 4
=> -2S = -40
=> S = 20
Find R:
=> R = 2S
=> R = 2(20)
=> R = 40
Therefore, Rita is 40, her son is 20.