The length of a rectangle is 3 more than 4 times it's width. the perimeter of the rectangle is 86 inches. what is the length of the rectangle?

Since the smaller value is the width, make the width=x. Since the length is 3 more than 4 times the width, that would be equal to 3+4x. Perimeter is equal to the sum of all sides. That would be x+x+3+4x+3+4x. Perimeter is equal to 86. Therefore, x+x+3+4x+3+4x=86. Combine like terms. 10x+6=86. Subtract 6 from both sides giving you 10x=80. Divide by 10 giving you x=8. That means that the width is 8!!! The length is 3+4x. Substitute 8 for x giving you 3+4*8. Multiply. 3+32. Add. 35 is the length.