(2m-3n)² - 15n²+10mn
4m²-12mn+9n²-15n²+10mn=4m²-2mn-6n²=2(2m²-mn-3n²)
c^n+c^(n+2) + 1 +c² =c^n+c^n*c²+1+c²=c^n(1+c²)+(1+c²)=(1+c²)(c^n+1)
<em>0.4*(6n-7)=0.5*(3n+7)</em>
<em>2.4n-2.8=1.5n+3.5</em>
<em>2.4n-1.5n=2.8+3.5</em>
<em>0.9n=6.3</em>
<em>n=6.3/0.9</em>
<em>n=63/9</em>
<em>n=7</em>
<em />
<em />
<span>(2/3х-4/5)*15=8
</span><span>2/3х-4/5=8\15
2\3х=8\15+4\5
</span>2\3х=8\15+12\15
2\3х=20\15
х=20\15*3\2
х=10\5=2