4х - 5у = 1 4х-5у =1
2х-3у=2 | * -2 -4х +6у = -4
- 5 у+ 6у = -3 4х - (-3) *5 = 1
у = -3 4х + 15 = 1
4х = -16
х = -4
Ответ(-4;-3)
а) 2,10,50... q = 10 : 2 = 5; ![b_{n+1}=b_n\cdot 5](https://tex.z-dn.net/?f=b_%7Bn%2B1%7D%3Db_n%5Ccdot+5)
<em>2; 10; 50; 250; 1250; 6250...</em>
б) 9,3,1... ![q = 3 : 9 = \dfrac13;~~~~b_{n+1}=b_n\cdot \dfrac13](https://tex.z-dn.net/?f=q+%3D+3+%3A+9+%3D+%5Cdfrac13%3B~~~~b_%7Bn%2B1%7D%3Db_n%5Ccdot+%5Cdfrac13)
![\boldsymbol{9; ~3; ~1; ~\dfrac13; ~\dfrac19; ~\dfrac1{27}...}](https://tex.z-dn.net/?f=%5Cboldsymbol%7B9%3B+~3%3B+~1%3B+~%5Cdfrac13%3B+~%5Cdfrac19%3B+~%5Cdfrac1%7B27%7D...%7D)
в) -1000,100,-10... q=100:(-1000)= -0,1; ![b_{n+1}=b_n\cdot (-0,1)](https://tex.z-dn.net/?f=b_%7Bn%2B1%7D%3Db_n%5Ccdot+%28-0%2C1%29)
<em>-1000; 100; -10; 1; -0,1; 0,01 ...</em>
г)
![\dfrac1{16};~-\dfrac18;~\dfrac14...~~~~~q=-\dfrac18:\dfrac1{16}=-2;~~~~b_{n+1}=b_n\cdot (-2)\\\\ \boldsymbol{\dfrac1{16};~-\dfrac18;~\dfrac14; -~\dfrac12; 1; -2...}](https://tex.z-dn.net/?f=%5Cdfrac1%7B16%7D%3B~-%5Cdfrac18%3B~%5Cdfrac14...~~~~~q%3D-%5Cdfrac18%3A%5Cdfrac1%7B16%7D%3D-2%3B~~~~b_%7Bn%2B1%7D%3Db_n%5Ccdot+%28-2%29%5C%5C%5C%5C+%5Cboldsymbol%7B%5Cdfrac1%7B16%7D%3B~-%5Cdfrac18%3B~%5Cdfrac14%3B+-~%5Cdfrac12%3B+1%3B+-2...%7D)
Нужно просто вынести переменную
1) -6ab+9b2=3b(-2a+3b)
2) x^2y-xy^2=xy(x-y)
3) -p^2q^2-pq= pq(-pq-1)