Irene R. answered 11/27/19
BS in Mechanical Engineering and Certified math teacher for 13 years
Let's use the variable e to represent Elga's age. Since Alvin is 7 years older than Elga, we write the following expression to represent Alvin's age: e + 7
The problem tells us that the sum of their ages is 95. Therefore we can write the following equation for the sum:
Elga's age + Alvin's age = 95
Then, using our variable expressions:
e + e + 7 = 95
Now use combining like terms and inverse operations to solve the equation:
e + e + 7 = 95
2e + 7 = 95
2e + 7 - 7 = 95 - 7
2e = 88
2e/2 = 88/2
e = 44 Elga is 44 years old
Alvin is 7 years older or 44 + 7 = 51 years old
The sum of their ages is 44 + 51 or 95 years.