(x-1)/3 = (x+1)/7 cross multiply
7(x-1) =3(x+1) distribute
7x-7 =3x+3 subtract 3x from both sides and add 7 to both sides
4x=10 divide both sides by 4
x=10/4
Hope the solution helped. Sometimes you need more than a solution. Contact fcabanski@hotmail.com for online, private tutoring, or personalized problem solving (quick for groups of problems.)