[D2]

For the purpose of the equations, I’ll call Andre and Bob a and b respectively.

a – 20 = b + 20 (equation 1)

2(b – 22) = a + 22 (equation 2)

We can juggle those around for

a = b +40 (equation 1r (re-arranged)) and

2b – 44 = a + 22 so 2b – 66 = a (equation 2r (rearranged))

The equations are now:

a = b + 40 (new equation 1) and

a = 2b – 66 (new equation 2)

Substitute from new equation 1 to new equation 2:

b + 40 = 2b – 66 so 40 = b – 66 making b = 106.

Plug b = 106 into new equations 1 and 2 for:

a = 106 + 40 (new equation 1) and

a = 212 – 66 (new equation 2)

This gives a = 146 and b = 106