Math Problem Statement

Solve this equation using substitution

Solve this equation using substitution

Solution

To solve the system of equations using substitution, here are the equations from the image:

  1. 8x+3y=48x + 3y = 4
  2. 7x+5y=34-7x + 5y = -34

Step 1: Solve one equation for one variable

From the first equation (8x+3y=48x + 3y = 4), solve for yy in terms of xx:

3y=48x3y = 4 - 8x y=48x3y = \frac{4 - 8x}{3}

Step 2: Substitute yy into the second equation

Substitute y=48x3y = \frac{4 - 8x}{3} into the second equation (7x+5y=34-7x + 5y = -34):

7x+5(48x3)=34-7x + 5\left(\frac{4 - 8x}{3}\right) = -34

Simplify the terms: 7x+5(48x)3=34-7x + \frac{5(4 - 8x)}{3} = -34 7x+2040x3=34-7x + \frac{20 - 40x}{3} = -34

Combine the terms under a common denominator: 21x3+2040x3=34\frac{-21x}{3} + \frac{20 - 40x}{3} = -34 21x+2040x3=34\frac{-21x + 20 - 40x}{3} = -34

Combine like terms: 61x+203=34\frac{-61x + 20}{3} = -34

Step 3: Solve for xx

Multiply through by 3 to eliminate the fraction: 61x+20=102-61x + 20 = -102

Subtract 20 from both sides: 61x=122-61x = -122

Divide by 61-61: x=2x = 2

Step 4: Solve for yy

Substitute x=2x = 2 back into y=48x3y = \frac{4 - 8x}{3}: y=48(2)3y = \frac{4 - 8(2)}{3} y=4163y = \frac{4 - 16}{3} y=123y = \frac{-12}{3} y=4y = -4

Final Solution:

The solution to the system of equations is: x=2,  y=4x = 2, \; y = -4


Would you like a step-by-step verification or have any questions about this process?


Here are 5 related questions to expand your understanding:

  1. What are other methods to solve a system of linear equations (e.g., elimination)?
  2. How can you verify the solution to a system of equations?
  3. What happens if a system of equations has no solution or infinitely many solutions?
  4. How can you graphically interpret the solution to this system of equations?
  5. How would you solve this system if decimals or fractions appeared in the original equations?

Tip: Always double-check your solution by substituting it back into both original equations!

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Math Problem Analysis

Mathematical Concepts

Linear Equations
System of Equations
Substitution Method

Formulas

y = (c - ax) / b (used to isolate y)
Substitution of one equation into the other
Basic arithmetic operations and solving linear equations

Theorems

Properties of equality
Solving systems of linear equations

Suitable Grade Level

Grade 8-10