Question

Solve these simultaneous equations by substitution method

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Answer 1

Answer:

x = -1

y = 3

Step-by-step explanation:

x + y = 2

x = 2 - y

2x² + xy + 1 = 0

2(2 - y)² + (2 - y)y + 1 = 0

2(4 + y² - 4y) + 2y - y² + 1 = 0

2y² - 8y + 8 - y² + 2y + 1 = 0

y² - 6y + 9 = 0

y² - 2*y*3 + 3² = 0

(y - 3)² = 0

y - 3 = 0

y = 3

x + 3 = 2

x = -1