1)
5^(x+1)+5^(x)=5³*6
6*5³=6*5^(x)
x=3
2)
5^x>5⁴
x>4
x∈(4;∞)
3)
5^(x+2)=125
5^(x+2)=5³
x+2=3
x=1
1.
2x^2-11x+12=0
D=121-96=25
x1=(11+5)/4=4
x2=(11-5)/4=1,5
2.
-3x^2-x+8=x^2-6x+9
-4x^2+5x-1=0
4x^2-5x+1=0
D=25-16=9
x1=(5+3)/8=1
x2=(5-3)/8=0,25
3.
-x^2+3x+55=x^2+14x+49
-2x^2-11x+6=0
2x^2+11x-6=0
D=121+48=169
x1=(-11+13)/4=0,5
x2=(-11-13)/4=-6