Step-by-step explanation:
The area of triangle is
=21×height×base=21×3×4=3×2=6 cm2
the first one is the answer to #1
and the second one is the answer to #2
Call Dawn's wage x, we will have Vesna's wage = x + 17 and Chris' wage = 4x(x + 17). So we have the equation:

Therefore, Chris's wage: