Question

{4 в степени х +4в степени у=80
{х+у=5

Answer 1

x+y=5⇒y=5-x
4^x+4^y=80
4^x+4^(5-x)=80
4^x+1024/4^x-80=0
4^2x-80*4^x+1024=0
4^x=a
a²-80a+1024=0
a1+a2=80 U a1*a2=1024
a1=16⇒4^x=16⇒x=2⇒y=5-2=3
a2=64⇒4^x=64⇒x=3⇒y=5-3=2
(2;3);(3;20