Question

СРОЧНО! даю 15 балов. Задачу и 2ое уравнения. ПЛИЗ

Answer 1

$1.\\1\frac12x-2\frac15=12.8-3.5x\\1.5x-2.2=12.8-3.5x\\1.5x+3.5x+12.8+2.2\\5x=15\\x=3\\\\2.\\(4.1x+2.5)-(2.3x+3.9)=1.6x\\4.1x+2.5-2.3x-3.9=1.6x\\1.8x-1.6x=1.4\\0.2x=1.4\\x=7\\\\3.\\x-10=2x-30\\2x-x=30-10\\x=20$