Update index.html

Schematic

Author: Gmac4247

index.html

@@ -870,7 +870,7 @@ <h3 itemprop="name" style="margin:7px">Area of a Square</h3>
 <section itemscope itemtype="http://schema.org/MathSolver" id="volume">
 <h3 itemprop="name" style="margin:7px">Volume of a Cube</h3>
 <br>
-<figure class=" imgbox"http://schema.org/ImageObject>
+<figure class="imgbox" itemscope itemtype="http://schema.org/ImageObject">
     <img class="center-fit" src="cubeMarkup.jpeg" alt="A cube is a 3 dimensional solid shape with 3 equal perpendicular pairs of parallel straight edges. V = edge × edge × edge = edge³">
     </figure>
 <br>
@@ -915,6 +915,7 @@ <h3 itemprop="name" style="margin:7px">Volume of a Cube</h3>
 </details>
 </section>
 </details>
+</section>
 <br>
 <br>
 <br>
@@ -929,7 +930,8 @@ <h3 itemprop="name" style="margin:7px">Area of a Triangle</h3>
 <br>
 <p itemprop="description" style="margin:12px">The square root of half of the area of the rectangle is the side length of the theoretical square that has the same area as the triangle.</p>
 <br>
-<math itemprop="mathExpression" style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML">
+<div itemprop="mathExpression">
+<math style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML">
  <mrow>
  <mi>A</mi>
 <mo>=</mo>
@@ -946,6 +948,7 @@ <h3 itemprop="name" style="margin:7px">Area of a Triangle</h3>
  </mrow>
 </math>
 </div>
+</div>
 <br>
 <br>
 <br>
@@ -1701,7 +1704,7 @@ <h2 itemprop="about" style="margin:7px">Trigonometry</h2>
 <br>
 <br>
 <br>
-<section itemscope itemtype="http://schema.org/MathSolver" itemref="triangle; trigonometry" id="polygon">
+<section itemscope itemtype="http://schema.org/MathSolver" itemref="triangle trigonometry" id="polygon">
 <h3 itemprop="name" style="margin:7px">Area of a regular Polygon</h3>
 <br>
 <figure class="imgbox" itemscope itemtype="http://schema.org/ImageObject">
@@ -1997,10 +2000,9 @@ <h3 itemprop="name" style="margin:7px">The Area of a Circle</h3>
 </mrow>
 </mrow>
 </math>
-</div>
 <br>
 <br>
-<section itemprop="description" itemref="trigonometry" id="circle_area_proof">
+<section itemref="trigonometry" id="circle_area_proof">
 <details>
   <summary><h4 style="margin:7px">When the overlapping area equals to the uncovered area in the middle, the sum of the areas of the quadrants is equal to the area of the square. That square represents the area of the circle in square units.
 </h4></summary>
@@ -2425,7 +2427,8 @@ <h3 itemprop="name" style="margin:7px">The Area of a Circle</h3>
 The area of both the square and the sum of the quadrants equals 16 right triangles with legs of a quarter, and a half of the square's sides, and its hypotenuse equal to the radius of the circle. 
 </p>
 <br>
-<math itemprop="mathExpression"> style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML">
+<div itemprop="mathExpression">
+<math style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML">
 <mrow>
 <mi>A</mi>
 <mo>=</mo>
@@ -2448,6 +2451,7 @@ <h3 itemprop="name" style="margin:7px">The Area of a Circle</h3>
 </msup>
 </mrow>
 </math>
+</div>
 <br>
 <br>
 <div id="circle_area_calculator">
@@ -4440,7 +4444,7 @@ <h3 itemprop="name" style="margin:7px">The volume of a square frustum pyramid ca
 </math>
 <br>
 <br>
-<math itemprop="description" style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML" >
+<math style="margin:12px" xmlns="http://www.w3.org/1998/Math/MathML" >
      <mrow>
  <mi>b</mi>
       <mo>=</mo>