解:移項(xiàng)得???$：3x-x>4+2，$??? 合并得???$：2x>6，$??? 所以???$x>3$??? 解:兩邊乘以???$-\frac 52$???得: ???$x\leqslant -\frac 52$??? 解:移項(xiàng)得???$x+3x\leqslant 11-3$??? 合并得???$4x\leqslant 8$??? 所以???$x\leqslant 2$??? 解:移項(xiàng)得???$：3x+4x\geqslant 1+2，$??? 合并得???$：7x\geqslant 3$??? 所以???$x \geqslant \frac 37$??? 解:∵???$2-x 的值不大于 2 x+3 的值 $??? ∴???$2-x \leqslant 2 x+3 $??? ∴???$-x-2 x \leqslant 3-2 $??? ∴???$-3 x \leqslant 1 $??? ∴???$x \geqslant-\frac {1}{3}$???
?$解:因?yàn)閍、b是整數(shù),所以a-2b、2a+3b-19也是整數(shù).\\由x+2b>a,解得x>a-2b.由x-3b+19<2a,解得x<2a+3b-19.\\由題意可得\left\{\begin{array}{l}a-2b+1=8,\\2a+3b-19-1=8,\end{array}\right.解得\left\{\begin{array}{l}a=11,\\b=2\end{array}\right.\\$? $解:(1)解方程組\left\{\begin{array}{l}x-y=4m,\\2x+y=2m+3\end{array}\right.得\left\{\begin{array}{l}x=2m+1,\\y=1-2m,\end{array}\right.\\因?yàn)閤-2y<8,所以2m+1-2(1-2m)<8,解得m<\frac{3}{2}\\(2)因?yàn)閙<\frac{3}{2},m為正整數(shù),所以m=1.\\所以原式=2m^{2}-2m+2-3m^{2}-6m+15=-m^2-8m+17.\\當(dāng)m=1時(shí)，原式=-1-8+17=8\\$
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