Abbas K. answered 12/31/19
PhD in Pharmacology with 7+ Years of Expert Teaching Experience
Hello Students,
This algebra question involves finding two unknowns, which is Carey's age and Donovan's age. In order to solve for two unknowns, we need to set up two equations relating the two unknowns and then solve it to find one of the unknowns first and then the second unknown.
Here, let the first unknown (Carey's present age) be denoted as 'C' and likewise, Donovan's present age be 'D'.
Now, let's set up the equations based on the information given.
Since, Carey is 12 years older than Donovan:
C = D + 12 ------------- Equation 1
Also, 5 years ago, their ages totaled up to 28 years:
(C - 5) + (D - 5) = 28 ------------- Equation 2
Where, (C - 5) and (D - 5) are Carey's and Donovan's ages 5 years ago (since C and D are their present ages)
Now, in equation 2, we substitute C as (D + 12) ---- using equation 1
Therefore,
[ (D+12) - 5 ] + (D-5) = 28
Solving for D...
[ D + 7 ] + (D - 5) = 28
2D + 2 = 28
2D = 26
Therefore, D = 13
Putting D = 13 in equation 1, we get:
C = 25
Hope this helps! Good luck! :)