Problem Analysis:
The task involves solving a system of linear equations using the
substitution method. The given system of equations is:
1. \( y = 2x - 3 \)
2. \( x + y = 5 \)
We are asked to solve for \( x \) and \( y \), and then verify our solution by substituting back into both equations.
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Step-by-Step Solution:
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Step 1: Understand the substitution method
The substitution method involves solving one equation for one variable (in this case, \( y \) is already solved in terms of \( x \) in the first equation) and substituting that expression into the other equation to solve for the remaining variable.
####
Step 2: Substitute \( y = 2x - 3 \) into the second equation
The second equation is:
\[ x + y = 5 \]
Substitute \( y = 2x - 3 \) into this equation:
\[ x + (2x - 3) = 5 \]
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Step 3: Simplify and solve for \( x \)
Combine like terms:
\[ x + 2x - 3 = 5 \]
\[ 3x - 3 = 5 \]
Add 3 to both sides:
\[ 3x = 8 \]
Divide by 3:
\[ x = \frac{8}{3} \]
####
Step 4: Solve for \( y \) using \( y = 2x - 3 \)
Now that we have \( x = \frac{8}{3} \), substitute this value into the equation \( y = 2x - 3 \):
\[ y = 2\left(\frac{8}{3}\right) - 3 \]
Simplify:
\[ y = \frac{16}{3} - 3 \]
Convert 3 to a fraction with a denominator of 3:
\[ y = \frac{16}{3} - \frac{9}{3} \]
\[ y = \frac{7}{3} \]
####
Step 5: Write the solution as an ordered pair
The solution to the system of equations is:
\[ \left( x, y \right) = \left( \frac{8}{3}, \frac{7}{3} \right) \]
####
Step 6: Verify the solution
To verify, substitute \( x = \frac{8}{3} \) and \( y = \frac{7}{3} \) back into both original equations.
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Verify in the first equation: \( y = 2x - 3 \)
\[ y = 2\left(\frac{8}{3}\right) - 3 \]
\[ y = \frac{16}{3} - 3 \]
\[ y = \frac{16}{3} - \frac{9}{3} \]
\[ y = \frac{7}{3} \]
This is correct.
#####
Verify in the second equation: \( x + y = 5 \)
\[ x + y = \frac{8}{3} + \frac{7}{3} \]
\[ x + y = \frac{15}{3} \]
\[ x + y = 5 \]
This is also correct.
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Final Answer:
The solution to the system of equations is:
\[
\boxed{\left( \frac{8}{3}, \frac{7}{3} \right)}
\]
Parent Tip: Review the logic above to help your child master the concept of synthetic division practice worksheet.