A rectangle has an area of21x+81square units. If the width is 3 units, what is the length of the rectangle?

The length of the rectangle is 7x + 27

Step-by-step explanation:

Given;

area of the rectangle, A = 21x + 81 units²

width of the rectangle, w = 3 units

let the length of the rectangle, = L

Area of the rectangle = length x width

A = L x w

21x + 81 = 3L

L = ¹/₃(21x + 81)

L = 7x + 27

Therefore, the length of the rectangle is 7x + 27

arrange the equations with like terms in columns.

analyze the coefficients of x or y.

add the equations and solve for the remaining variable.

substitute the value into either equation and solve.

check the solution.

step-by-step explanation: