Question

resolva os sistemas x + y=60 e 5 x - y = 210

Answer 1

X+Y=60
5X-Y=210

X=60-Y

5.(60-Y)-Y=210
300-5Y-Y=210
300-6Y=210
6Y=210-300
6Y= -90
Y= -90/6
Y= -15
X=60-Y
X=60-15
X=45