1)27x^6y³*5y^7=135x^6y^10
2)16a^4b^20*25a^14b^4=400a^18b24
3)5/2*4/25a^5b^5=0,4(ab)^5=0,4*1^5=0,4*1=0,4
4)576m^10n^6 : 1728m^9n^3=1/3mn³
5)x²-6x-1=6+x²+x
x²-6x-1-6-x²-x=0
-7x=7
x=-1
<span>2x-3y=11 </span>
<span>5x+y=2</span>
<span>у=2-5х</span>
<span>2х-3(2-5х)=11</span>
<span>2х-6+15х=11</span>
17х=17
х=1
у=-3
Ответ: (1; -3)
(0,2a-1,3b)(0,2a-1,3b) = (0,2a-1,3b)² =
=0,2²a²-2*0,2*1,3b+1,3²b²=
=0,04a²-0,52ab+1,69b²