4 years ago (k-4 and d-4) kevin was 5 times as old as dan
k-4=5(d-4)
we have k=3d and k-4=5(d-4) sub 3d for k in second euaiton 3d-4=5(d-4) 3d-4=5d-20 minus 3d both sides -4=2d-20 add 20 both sides 16=2d divide 2 8=d sub back k=3d k=3(8) k=24
Plug in 3D for the K values in the second equation.
3D - 4 = 5(D - 4) Use the Distributive Property 3D - 4 = 5D - 20 Add 4 to both sides 3D = 5D - 16 Subtract 5D from both sides -2D = -16 Divide both sides by -2 D = 8 Now, plug that D value into the original equation.
K = 3D Plug in the D value K = 3(8) Multiply K = 24
Finally, you can double check your math.
4 years ago, Daniel would've been 4 and Kevin would be 20, so Kevin would've been 5 times as old as Daniel. And 8 x 3 = 24.
