Question

ПОМОГИТЕ ПЖ СРОЧНО ДАЮ 40 БАЛЛОВ

прогрессия ,найти х​

Answer 1

$\displaystyle\bf\\1)\\\\\left \{ {{a_{17} =3x+1} \atop {a_{7} =2x}} \right.\\\\\\-\left \{ {{a_{1} +16d=3x+1} \atop {a_{1}+6d =2x}} \right.\\-----------\\10d=3x+1-2x\\\\10d=x+1\\\\\boxed{d=\frac{x+1}{10}} \\\\2)\\\\\left \{ {{a_{25} =4x-1} \atop {a_{17} =3x+1}} \right.\\\\\\-\left \{ {{a_{1}+24d =4x-1} \atop {a_{1} +16d=3x+1}} \right.\\------------\\8d=4x-1-3x-1\\\\8d=x-2\\\\\boxed{d=\frac{x-2}{8} }\\\\\\\frac{x+1}{10} =\frac{x-2}{8} \\\\\\10x-20=8x+8\\\\10x-8x=8+20$

$\displaystyle\bf\\2x=28\\\\\boxed{x=14}$