Understanding the Context

What Does the Equation 2(3) + 3d = 15 Mean?

The equation 2(3) + 3d = 15 combines arithmetic and variables to form a linear relationship. At first glance, it includes constants and a variable term 3d, but simplifying known parts makes it easier to isolate d.

Step-by-Step Solution: From 2(3) + 3d = 15 to d = 3

Key Insights

Step 1: Simplify the Constant Term

Start by calculating any multiplication on the left side:
2(3) = 6, so the equation becomes:
6 + 3d = 15

Step 2: Isolate the Variable Term

Subtract 6 from both sides to remove the constant:
3d = 15 – 6 → 3d = 9

Step 3: Solve for d

To find d, divide both sides by 3:
d = 9 ÷ 3 → d = 3

Why This Process Works (Conceptual Understanding)

Final Thoughts

Every step follows fundamental rules of algebra:

• Multiplication is commutative, so 2(3) = 3(2) = 6
  
• Equality preserves balance — operations applied to both sides keep the equation true
  
• Isolating variables allows direct value determination

This structure ensures the solution d = 3 satisfies the original equation:
Plugging back: 2(3) + 3(3) = 6 + 9 = 15

Why Learning This Matters

Mastering simple algebraic manipulations builds confidence and paves the way for tackling more complex equations. Recognizing patterns like combining constants first, then isolating the variable, is a skill used throughout math, science, and engineering.