Answer:
6x - 12
Step-by-step explanation:
In this question, we area asked to write an expression for a mother’s age given some information about the children’s age. We proceed as follows:
Charlie is x years old and his sister is 4 years younger. His sister’s age would be x -4. The total of both ages would be their addition and that is x + x - 4 = 2x - 4
Now, the mother’s age is 3 times this quantity.
Mathematically, that is 3(2x -4) = 6x -12
The expression of the mother’s age is (6x-12) years
