Solving the Linear Equation: 0.2x + 0.8(5 - x) = 0.5 × 5 – A Step-by-Step Guide

Understanding linear equations is a fundamental skill in algebra, essential for students and professionals alike. One commonly encountered equation is:

0.2x + 0.8(5 - x) = 0.5 × 5

Understanding the Context

In this comprehensive article, we’ll break down this equation step-by-step, solve it clearly, and explore its real-world applications. Whether you're preparing for exams, teaching algebra, or solving practical problems, this guide will help you master the equation.


Understanding the Equation

The equation
0.2x + 0.8(5 - x) = 0.5 × 5
combines linear expressions involving a variable x and arithmetic operations. Let's rewrite and simplify each side to clarify the problem.

Key Insights

First, simplify the right-hand side:
0.5 × 5 = 2.5
So, the equation becomes:
0.2x + 0.8(5 - x) = 2.5


Step 1: Expand the Parentheses

Distribute 0.8 across (5 - x):
0.8 × 5 = 4
0.8 × (-x) = -0.8x
Thus:
0.2x + (4 - 0.8x) = 2.5


Final Thoughts

Step 2: Combine Like Terms

Combine the x terms:
0.2x - 0.8x = -0.6x
So:
-0.6x + 4 = 2.5


Step 3: Isolate the Variable Term

Subtract 4 from both sides:
-0.6x = 2.5 - 4
-0.6x = -1.5


Step 4: Solve for x

Divide both sides by -0.6:
x = -1.5 / (-0.6) = 2.5


Final Answer