Question

How would you use equations to calculate the age of Al given that Al's father is 45 and he is 15 years older than twice Al's age?

Answer 1

Let `x` be Al's age, and `y` be Al's father age. From your statement, we know that:

• `y=45` (Al's father is 45)
• `y=2x+15` (if you take Al's age and double it, Al's father is 15 older than that)

Combining the two expression, we observe that 45 and `2x+15` are both equal to `y`, and thus must be equal. So, from `45=2x+15` you easily get `2x=30`, and finally, `x=15`