Hello, 2(l+w)=78 Divided 2 from both side 2(l+w)/2=78/2 l+w=39 feet
l=6w+4 Replace l with 6w+4
6w+4+w=39 7w+4=39 Subtract 4 from both side 7w=35 Divided 7 from both side w=5 feet l=6w+4 l=6(5)+4 l=30+4 l=34 feet. As a result, the length of the rectangle is 34 feet and the width of rectangle is 5 feet. Hope it help!