Question

The pair of equations 3^x+y=81 81^x-y=3 it has what solution

Answer 1

Answer:

x= 1

Step-by-step explanation:

When base have same value then comparison of power takes place.

Answer 2

Answer:

Step-by-step explanation:

3^x+y=81 ................(1)

81^x-y=3.................(2)

adding

3^x+81^x=84

3^x+((3)^4)^x=84

3^x+(3^x)^4=84

let 3^x=z

so z^4+z-84=0

putting z=3

we get z^4+z-84

=81+3-84=0

so z-3 is a factor of z^4+z-84

so z=3

3^x=3

x=1

puttinx x=1 in(1)

3^1+y=81

y=81-3=78

so x=1,y=78