Answer:
The two numbers are:
8 and 13
Step-by-step explanation:
a = 2b - 3 Eq. 1
a + b = 21 Eq. 2
Replacing Eq. 1 in Eq. 2:
(2b-3) + b = 21
3b - 3 = 21
3b = 21 + 3
3b = 24
b = 24/3
b = 8
from Eq. 1
a = 2*8 - 3
a = 16 - 3
a = 13
Check:
From Eq. 2:
a + b = 21
13 + 8 = 21