Question

1. Sarah's age is twice that of her sister. When you add Sarah's age to her sister's age, you get 33. How old is

Answer 1

Answer:

x+2x=33

3x=33

x=11

Sara's sisiter is 11

Sarah is (11 times 2) 22

Answer 2

For this case we have:

x: Variable that represents Sarah's age

y: Variable that represents the age of your sister

So:

$x = 2y\\y + x = 33$

Substituting the first equation in the second we have:

$y + 2y = 33\\3y = 33\\y = \frac {33} {3}\\y = 11$

So, Sarah's sister is 11 years old.

$x = 2y = 2 (11) = 22$

Sarah is 22 years old.

Answer:

$y + 2y = 33$ Where "y" is the age of Sarah's sister

Sarah's sister is 11 years old and Sarah is 22 years old.