feat: adds correct expressions into expression_calculator.ts

Author: Edge-J

lesson_06/expression/.env.test

@@ -1 +1 @@
-HW_VERSION=your assigned version here
+HW_VERSION=D

lesson_06/expression/src/expression_calculator.ts

@@ -2,7 +2,13 @@ export class ExpressionCalculator {
   /** Returns a calculation involving a, b, c, d, and e */
   calculate(a: number, b: number, c: number, d: number, e: number): number {
     // Implement your code here to return the correct value.
-    return 0;
+    const sum = c + d;
+
+    const denominator = this.pow(sum, e);
+
+    const numerator = a * b;
+
+    return numerator / denominator;
   }
 
   pow(base: number, exponent: number): number {