The expression for the total number of cells in both dishes is given by;
2t² + 6t + 8 for t in minutes.
Explanation:
- For the first petri dish, t² + 4t + 4, take this as equation 1 while for the second petri dish, t² + 2t + 4, take this as equation 2.
- Let the total cells in both petri dishes be represented by equation 3. So equation 3 = equation 1 + equation 2. Equation 3; t² + 4t + 4 + t² + 2t + 4 = t² + t² + 4t + 2t + 4 + 4 = 2t² + 6t + 8.
- By substituting the values of t, we can determine if this equation is right.
- If t = 5, equation 1; 5² + 4×5 + 4 = 49, equation 2; 5² + 2×5 + 4 = 39. The sum is 49 + 39 = 88. So equation 3 becomes 2×5² + 6×5 + 8 = 50 + 30 + 8 = 88. Both the values are equal so equation 3 is correct.