Answer:
Trevor has 16 T-shirts
Step-by-step explanation:
Trevor's shirts (t) + Marisa's shirts(m)= 26
t + m = 26
m= t -6
Replace Marisa's (m ) by t-6 ( 6 fewer than Trevor)
t+ t - 6 = 26
2t - 6= 26
2t= 26+6
t = 32/2
t = 16
Trevor has 16 t-shirts
Marisa has 16 -6 t-shirts= 10
16+ 10 = 26