Question

If you add​ Natalie's age and​ Fred's age, the result is 39 If you add​ Fred's age to 3 times​ Natalie's age, the result is 69 Write and solve a system of equations to find how old Fred and Natalie are

Answer 1

Natalie is 15

Fred is 24

Explanation:

You would first create equations to represent the problem. You would then solve for a variable (I chose to solve for y). I subtracted each equation from each other which helped me isolate y, which equaled 15. I then substituted y for 15 which allowed me to isolate x, which gave me 24.

(the equations)

x + y = 39

x + 3y = 69

(solving for y)

x + 3y = 69 - x + y = 39

x-x +3y -y = 69 - 39

2y = 30

y = 15

(solving for x)

x + 15 = 39

x +15 -15 = 39 -15

x = 24