1) х=9, у=-2
2) х=3, у=4
3) х=-1, у=5
4) х=6, у=2
3) 5^3×10^-3/2^-10=5^3 × 2^-3 ×5^-3/ 2^-10= 2^7=128
4) в апреле 6°С
5) log_3 (-2x-7)=3
о.д.з.-2х-7>0
-2х >7
х<-3,5
-2x-7=3^3
-2x-7=27
-x=34÷2
x=-17
16,17,18,19,20,21,22,23. 79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156