Calculating Area of Shapes – Loan calculator

Area Calculator for Common Shapes

Use this calculator to quickly determine the area of squares, rectangles, circles, and triangles. Select your desired shape and enter the required dimensions.

Select Shape: Square Rectangle Circle Triangle

Side Length: units

Length: units

Width: units

Radius: units

Base: units

Height: units

Understanding Area and Its Calculation

Area is a fundamental concept in geometry, representing the amount of two-dimensional space a shape occupies. It's measured in square units (e.g., square meters, square feet, square inches) and is crucial in various fields, from construction and engineering to design and everyday problem-solving.

Why is Area Important?

Construction: Calculating the amount of flooring, paint, wallpaper, or roofing materials needed.
Gardening: Determining the size of a garden bed or the amount of fertilizer required.
Design: Laying out rooms, furniture, or graphic elements.
Real Estate: Valuing properties based on their square footage.

Formulas for Common Shapes:

1. Square

A square is a quadrilateral with four equal sides and four right angles. Its area is found by multiplying the length of one side by itself.

Formula: Area = Side × Side (or Side²)

Example: If a square has a side length of 5 units, its area is 5 × 5 = 25 square units.

2. Rectangle

A rectangle is a quadrilateral with four right angles, where opposite sides are equal in length. Its area is calculated by multiplying its length by its width.

Formula: Area = Length × Width

Example: A rectangular room with a length of 10 feet and a width of 8 feet has an area of 10 × 8 = 80 square feet.

3. Circle

A circle is a perfectly round shape where all points on the boundary are equidistant from the center. Its area depends on its radius (the distance from the center to any point on the circumference).

Formula: Area = π × Radius² (where π ≈ 3.14159)

Example: A circular garden bed with a radius of 3 meters has an area of π × 3² = 9π ≈ 28.27 square meters.

4. Triangle

A triangle is a polygon with three edges and three vertices. Its area is half of the product of its base and its height (the perpendicular distance from the base to the opposite vertex).

Formula: Area = 0.5 × Base × Height

Example: A triangular sail with a base of 6 feet and a height of 9 feet has an area of 0.5 × 6 × 9 = 27 square feet.

Our calculator simplifies these calculations, allowing you to quickly find the area for your specific needs.

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} .calculator-form .form-group { flex-direction: column; align-items: flex-start; } .calculator-form span { margin-left: 0; margin-top: 5px; } } function updateInputs() { var shape = document.getElementById("shapeSelector").value; var squareDiv = document.getElementById("squareInputs"); var rectangleDiv = document.getElementById("rectangleInputs"); var circleDiv = document.getElementById("circleInputs"); var triangleDiv = document.getElementById("triangleInputs"); squareDiv.style.display = "none"; rectangleDiv.style.display = "none"; circleDiv.style.display = "none"; triangleDiv.style.display = "none"; if (shape === "square") { squareDiv.style.display = "block"; } else if (shape === "rectangle") { rectangleDiv.style.display = "block"; } else if (shape === "circle") { circleDiv.style.display = "block"; } else if (shape === "triangle") { triangleDiv.style.display = "block"; } document.getElementById("resultDisplay").innerHTML = ""; // Clear previous result } function calculateArea() { var shape = document.getElementById("shapeSelector").value; var area = 0; var resultText = ""; var isValid = true; if (shape === "square") { var side = parseFloat(document.getElementById("sideLength").value); if (isNaN(side) || side <= 0) { resultText = "Please enter a valid positive side length."; isValid = false; } else { area = side * side; resultText = "The area of the square is: " + area.toFixed(2) + " square units."; } } else if (shape === "rectangle") { var length = parseFloat(document.getElementById("rectangleLength").value); var width = parseFloat(document.getElementById("rectangleWidth").value); if (isNaN(length) || length <= 0 || isNaN(width) || width <= 0) { resultText = "Please enter valid positive length and width."; isValid = false; } else { area = length * width; resultText = "The area of the rectangle is: " + area.toFixed(2) + " square units."; } } else if (shape === "circle") { var radius = parseFloat(document.getElementById("circleRadius").value); if (isNaN(radius) || radius <= 0) { resultText = "Please enter a valid positive radius."; isValid = false; } else { area = Math.PI * radius * radius; resultText = "The area of the circle is: " + area.toFixed(2) + " square units."; } } else if (shape === "triangle") { var base = parseFloat(document.getElementById("triangleBase").value); var height = parseFloat(document.getElementById("triangleHeight").value); if (isNaN(base) || base <= 0 || isNaN(height) || height <= 0) { resultText = "Please enter valid positive base and height."; isValid = false; } else { area = 0.5 * base * height; resultText = "The area of the triangle is: " + area.toFixed(2) + " square units."; } } var resultDisplay = document.getElementById("resultDisplay"); resultDisplay.innerHTML = resultText; if (!isValid) { resultDisplay.style.backgroundColor = "#f8d7da"; resultDisplay.style.borderColor = "#f5c6cb"; resultDisplay.style.color = "#721c24"; } else { resultDisplay.style.backgroundColor = "#e9f7ef"; resultDisplay.style.borderColor = "#d4edda"; resultDisplay.style.color = "#155724"; } } // Initialize inputs on page load window.onload = function() { updateInputs(); 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