X*7+y*3.5=2170 x+y=320

Question

X*7+y*3.5=2170 x+y=320

Answer 1

Х=320-у 7(330-у)+3,5у=2170 2240-7у+3,5у=2170 2240-3,5у=2170 3,5у=70 У=20 Х=300