Solve the pair of equations and by the method of substitution.
Answer
Step-by-step solution
- From the second equation, express as because substitution requires one variable in terms of the other.
- Substitute into the first equation: .
- Simplify: .
- Subtract 2 from both sides: .
- Divide by 5: .
- Substitute back into to get .
Common mistake: Forgetting to substitute correctly, leading to instead of .
Concept tested: Substitution method
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