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5 votes
Gabrielle is 5 years older than Mikhail. The sum of their ages is 45 . What is Mikhail's age?

User Evans
by
7.0k points

2 Answers

4 votes
Use a system of equations.

Age of Gabrielle: x
Age of Michael: y

x-5=y
x+y=45

x=y+5

(y+5)+y=45
2y+5=45
2y=40
y=20

Mikhail is 20 years old.

Hope this helps!
User AndyDunn
by
6.5k points
3 votes
g = Gabrielle
M = Mikhail

g + m = 45
g = m + 5

Input g into g + m = 45

(m+ 5) + m = 45
2m + 5 = 45
Subtract 5 from both sides.
2m = 40
Divide both sides by 2.
m = 20

Input m into g = m + 5

g = 20 + 5
g = 25

Mikhail is 20 years old.
User Lekroif
by
7.8k points