Đề bài sai rồi cậu ơi

\(\dfrac{5}{4}:x-\dfrac{1}{3}=\dfrac{1}{6}\)

\(\dfrac{5}{4}:x=\dfrac{1}{6}+\dfrac{1}{3}\)

\(\dfrac{5}{4}:x=\dfrac{1}{2}\)

\(x=\dfrac{5}{4}:\dfrac{1}{2}\)

\(x=\dfrac{5}{2}\)

\(15\cdot180\cdot2+1500+150\cdot27\cdot2\\ =\left(15\cdot2\right)\cdot180+\left(15\cdot2\right)\cdot50+15\cdot2\cdot10\cdot27\\ =30\cdot180+30\cdot50+30\cdot270\\ =30\cdot\left(180+50+270\right)\\ =30\cdot500\\ =15000\)

\(\left(x+2y\right)^2=x^2+2\cdot x\cdot2y+\left(2y\right)^2=x^2+4xy+4y^2\)

\(\dfrac{-4\cdot75^2+4\cdot72^2}{\left(-18\right)^2}\\ =\dfrac{-4\cdot3^2\cdot25^2+4\cdot3^2\cdot24^2}{18^2}\\ =\dfrac{-36\cdot\left(25^2-24^2\right)}{18^2}\\ =\dfrac{18\cdot\left(-2\right)\cdot49}{18^2}\\ =\dfrac{-49}{9}\)

Ta có:

\(A=-3x^2-12x-12\\ =-3\left(x^2+4x+4\right)\\ =-3\left(x+2\right)^2\)

Vì: \(\left(x+2\right)^2\ge0\forall x\rightarrow-3\left(x+2\right)^2\le0\forall x\)

Dấu "=" xảy ra khi: \(x+2=0\)

\(\Rightarrow x=-2\)

Vậy: GTLN của A là: \(0\) tại \(x=-2\)

Số tiền lãi là:

\(7500000\times15\%=1125000\) (đồng)

Đáp số: \(1125000\) đồng

\(\left(3x-1\right)^3=125\\ \Rightarrow\left(3x-1\right)^3=5^3\\ \Rightarrow3x-1=5\\ \Rightarrow3x=5+1\\ \Rightarrow3x=6\\ \Rightarrow x=6:3\\ \Rightarrow x=2\)

\(\dfrac{2023}{2016}=1+\dfrac{7}{2016}\)

\(\dfrac{2016}{2009}=1+\dfrac{7}{2009}\)

Vì: \(\dfrac{7}{2016}< \dfrac{7}{2009}\) nên \(\dfrac{2023}{2016}< \dfrac{2016}{2009}\)

\(a,x+12=34\\ x=34-12\\ x=22\)

\(b,124+\left(2012+2x\right)=300\\ 2012+2x=300-124\\ 2012+2x=176\\ 2x=176-2012\\ 2x=-1836\\ x=-1836:2\\ x=-918\)

\(c,\left[\left(x+32\right)-17\right]\cdot2=42\\ x-15=42:2\\ x-15=21\\ x=21+15\\ x=36\\\)

\(d,2x+x=2^3\cdot3\\3x=8\cdot3\\ 3x=24\\ x=24:3\\ x=8 \)