Solve the simultaneous equations: and .
Answer and explanation
Correct answer: D. and
- Step 1: Substitute the linear equation into the quadratic equation: .
- Step 2: Factorise the quadratic equation: or .
- Step 3: Substitute each back into the linear equation : when , ; when , . Solutions are and .
Answer
and .
Why not the others: arises from an algebraic sign error when factorising ; and do not satisfy the circle equation .
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