Practice question · Select all that apply
The system 'x + y = 4, 2x + 2y = 8' has infinitely many solutions. Select every pair (x, y) that is a solution.
Hints
- Both equations reduce to the same line x + y = 4.
- A pair is a solution exactly when its coordinates add to 4.
Show the answer
- A. (0, 4)
- B. (4, 0)
- C. (1, 3)
- E. (-1, 5)
Why
The second equation is just twice the first, so every point with x + y = 4 solves the system. (0,4), (1,3), (4,0) and (-1,5) all sum to 4; (2,3) sums to 5 and fails.
Practise Systems of Linear Equations
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