A^10*a^15=a^25
a^16:a^11=a^5
a^7*a^3=a^10
3^5*x^5=(3x)^5
a^4:5^4=(a:5)^4
10^6x=1000
10^6x=10^3
6x=3
x=3/6=1/2
1) 1.8x+0.3y=0.3(6x+y)=0.3(-12+3)=0.3*(-9)=-2.7
2) 2.6x-0.2y=0.2(13x-y)=0.2(-26-3)=0.2*(-29)=-5.8
3х²-6х-3х-х²=-2х+8-4
2х²-9х+2х-4=0
2х²-7х-4=0
√Д=√7²-4×2×4=√49-24=√25=5
х1=-(-7)+5/2×2=12/4=3
х2=7-5/4=2/4=0,5
Y^2+2xy+x^2=x^2+2x+1
(x+y)^2=(x+1)^2
1)x+y=x+1
y=1
x- любое
2)x+y=-x-1
x=-(y+1)/2
гипотенуза=5 (cosa=3/5=0,6)
катет=4 (3*3+4*4=5*5)