Question

Как решить? Забылаааа

Answer 1

$1)\qquad 40-x=\frac{x}{3}\\\\40=x+\frac{x}{3}\\\\40=\frac{4x}{3}\\\\x=40:\frac{4}{3}\\\\x=\frac{40\cdot 3}{4}\\\\x=30\\\\ili\\\\2)\qquad 40-x=\frac{x}{3}\; \Big |\cdot 3\\\\120-3x=x\\\\120=4x\\\\x=120:4\\\\x=30$