Program Description: This program will calculate total usable area of a house by summing the square feet of rectangular rooms. This requires inputs in the form of length and width dimensions of each room to find the area of each room then adding those numbers together to find the area of all rooms. The results will be the output in area of each room and the total area of all the rooms.

Analysis:
The area of each room is found using the equation Area=Length x Width. The output in total square feet is found by summing the output of the individual rooms.
L = Length of room
W = Width of room
Area= (L) * (W)
R1 = Room 1, L1 * W1
R2 = Room 2, L2 * W2
R3 = Room 3, L3 * W3

Define 3 integer numbers as area of each room: R1, R2, R3
Usable area will store the sum in total square feet of R1, R2, R3

Test Plan
The following input is required for testing:
Test Case 1:
R1: L = 10, W = 12, L*W = 120
R2: L = 10, W = 10, L*W = 100
R3: L = 12, W = 12, L*W = 144
Usable Area: R1 + R2 + R3 = 364 square feet

Test Case 2:
R1: L = 10, W = 12, L*W = 120
R2: L = 11, W = 11, L*W = 121
R3: L = 12, W = 12, L*W = 144
Usable Area: R1 + R2 + R3 = 385 square feet

Pseudocode

// This program will add together the square feet of rooms to determine the total square feet of a house.

// Declare variables

Declare R1, R2, R3, Usable Area as Integer

// Set values of Integers

//The values for R will be found using L x W for each Room

Set R1 = 120
Set R2 = 100
Set R3 = 144
Set usable = R1+R2+R3

Set R1 = 108
Set R2 = 121
Set R3 = 144
Set usable = R1+R2+R3

// Print Total

Print R1, R2, R3, Usable