(2t+9)(9-2t)+ 4t²=81-4t^2+4t^2=81
1
log(5)1/25+log(√3)27=-2+6=4
2
log(0,5)4+log(√5)25=-2+4=2
3
2^(2x-4)=9
2x-4=log(2)9
2x=4+2log(2)3
x=2+log(2)3
4
5^(3x+6)=27
3x+6=log(5)27
3x=-6+3log(5)3
x=-2+log(5)3
7z^2-14zy+7y^2=7(z^2-2zy+y^2)=7*(z-y)^2
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