Ben is 3 times as old as daniel and is also 4 years older than daniel. how old is ben?

Ben - 3 * D
Ben - 3 + D 

B = 3D
B = 4 + D

Since B is the same amount and these are both equivalent to B we can set them equal to each other then solve for D. Once we know D we can plug it back into one of the equations to get B. 

3D = 4 + D

Get your like terms on one side (my recommendation is the smaller D value, because the larger one will lead the number to be negative, but it is up to you!)

3D - D = 4 + D - D

Simplify: 

2D = 4

Divide by 2 on both sides. 

2D/2 = 4/2

Simplify!

D = 4/2 = 2

Plug that back into one of the equations.

B = 3*D
B = 3*(2) 

Ben is, 6 years old! . 

It’s d for sure i just did also that’s why