Question

: Katie is 4 years younger than Sylvia. ​Let k represent Katie’s age, ​and let s represent Sylvia’s age.​ ​ ​Part A Using the variables defined above, write an equation that ​shows the relationship between Katie’s age and Sylvia’s age. ​ ​ ​Part B Use the equation from Part A to find how old Sylvia is when ​Katie is 13 years old. ​ ​​ years old.

Answer 1

Part A:
`k=s-4`

Part B: 17 years old.

Explanation:

Let be "k" Katie’s age, ​and "s" Sylvia’s age.

Part A

According to the information given, Katie is 4 years younger than Sylvia. This meanas that we can find Katie's age subtracting 4 years from Sylvia's age.

Therefore, we can write the following equation that ​shows the relationship between Katie’s age and Sylvia’s age:

`k=s-4`

Part B

In order to find Sylvia’s age when Katie is 13 years old, you must substitute
`k=13` into the equation and then solve for "s":

`13=s-4\\\\13+4=s\\\\s=17`