7^(x+2)-14·7^x=5,7²·7^x-14·7^x=5,49·7^x-14·7^x=5,35·7^x=5,7·7^x=1,7^x=1/7,7^x=(7)⁻¹,x=-1.10·5^(x-1)+5^(x+1)=7,10·(5^x)/5+(5^x)·5=7,2·5^x+5·5^x=7,7·5^x=7,5^x=1,5^x=(5)⁰,x=0.2^x+2^(x+1)+2^(x+2)+2^(x+3)=30,2^x+2·2^x+2²·2^x+2³·2^x·=30,2^x(1+2+4+8)=30,15·2^x=30,2^x=2,2^x=2¹,x=1.2^x+2^(x+1)+2^(x+2)=5^x+5^(x+1),2^x+2·2^x+2²·2^x=5^x+5·5^x,2^x(1+2+4)=5^x(1+5),6·2^x=6·5^x,2^x=5^x,2^x/5^x=1,(2/5)^x=(2/5)⁰,x=0.4^(x-1)+4^x+4^(x+1)=84,4⁻¹·4^x+4^x+4¹·4^x=84,4^x(1/4+1+4)=84,4^x(1+4+16)/4=84,(21/4)·4^x=84,4^x=84·4/21,4^x=16,4^x=4²,x=2.3^(x+2)-3^(x+1)+3^x=21,3²·3^x-3·3^x+3^x=21,3^x(9-3+1)=21,7·3^x=213^x=3,3^x=3¹,x=1.5·2^√x-3·2^(√x-1)=56,5·2^√x-3·2⁻¹·2^x=56,2^√x(5-3/2)=56,2^√x(5-1,5)=56,3,5·2^√x=56,2^√x=16,2^√x=2⁴,√x=4,(√x)²=4²,x=16.