Answer:
Step-by-step explanation: let the first number be x and the second number be y
according to the condition given
x+y=21
3x-y=43
using elimination method
3x+3y=63
3x-y=43
subtacting both the equations
4y=20
y=20/4
y=5
substituting value of y in eq 1
x+5=21
x=21-5
x=16
therefore x=16 and y=5
the two numbers are 16 and 5
