Final answer:
To solve this problem, we can set up a system of equations and solve graphically. The ages of Cho and her sister are 17 and 9, respectively.
Step-by-step explanation:
To solve this problem graphically, we need to set up a system of equations based on the given information. Let's represent Cho's age as x and her sister's age as y.
The first equation we can write is x + y = 26, since the sum of their ages is 26.
The second equation we can write is x = 2y + 5, since Cho's age is 5 more than twice her sister's age.
To solve this system of equations graphically, we can plot the lines corresponding to each equation on a graph and find the point of intersection, which represents the ages of both girls.
When we plot these lines, we can see that the point of intersection is (17, 9). Therefore, Cho is 17 years old and her sister is 9 years old.