Micheal is 12 years older than brandon. seventeen years ago, micheal was 4 times as old as brandon. how old is brandon now?

he is 21

Step-by-step explanation:

We can use the given information to write down two equations that describe the ages of Michael and Brandon.

Hint #22 / 11

Let Michael's current age be mm and Brandon's current age be bb.

Hint #33 / 11

The information in the first sentence can be expressed in the following equation:

\blue{m = b + 12}m=b+12

Hint #44 / 11

Seventeen years ago, Michael was m - 17m−17 years old, and Brandon was b - 17b−17 years old.

Hint #55 / 11

The information in the second sentence can be expressed in the following equation:

\red{m - 17 = 4(b - 17)}m−17=4(b−17)

Hint #66 / 11

Now we have two independent equations, and we can solve for our two unknowns.

Hint #77 / 11

Because we are looking for bb, it might be easiest to use our first equation for mm and substitute it into our second equation.

Hint #88 / 11

Our first equation is: \blue{m = b + 12}m=b+12. Substituting this into our second equation, we get the equation:

\blue{(b + 12)}\red{-17 = 4(b - 17)} (b+12)−17=4(b−17)

which combines the information about bb from both of our original equations.

Hint #99 / 11

Simplifying both sides of this equation, we get: b - 5 = 4 b - 68b−5=4b−68.

Hint #1010 / 11

Solving for bb, we get: 3 b = 633b=63.

Hint #1111 / 11

b = 21b=21.