Question

My brother is currently three times as old as me, but in five years, my brother

will only be twice as old as me. Create and solve a system of equations to
determine how old my brother is right now?

PLZ ANSWER QUICKLY!!!!

Answer 1

Answer: Your brother is 15 years old right now.

Explanation:

Let be "m" your currently age and "b" your brother's currently age.

Knowing that right now he is three times (this indicates multiplication) as old as you, you can write the following equation:

`b=3m`

In five years your age will be:

`m+5`

And your brother's age will be:

`b+5`

Then, if in five years, your brother will be twice as old as you, you can set up the second equation:

`b+5=2(m+5)`

Then, the System of equations is:

`\left \{ {{b=3m} \atop {b+5=2(m+5)}} \right.`

Apply the Substitution method and substitute the first equation into the second one and solve for "m":

`3m+5=2(m+5)\\\\3m+5=2m+10\\\\m=10-5\\\\m=5`

Substitute the value of "m" into the first equation and evaluate in order to find "b":

`b=3(5)\\\\b=15`