Question

1. Solve equations x - y = 3 and 4x + 2y = 0 for value of x and y?

(a) 1, 2 (b) 1,-2 (c) -1,-2 (d) -1,2​

Answer 1

$\huge\bold{\textbf{\textsf{{\color{cyan}{Question}}}}}$

$⇒ x - y = 3 \\ ⇒ 4x + 2y = 0 \: or \: (2x + y = 0) \\ \\ ⟶equation \: 1 + equation \: 2 \\ ⇒ 2x + y + x - y = 0 + 3 = 3 \\ \\ 3x = 3 \\ ∴x = \frac{3}{3} = 1 \\ substitute \: x = 1 \: in \: (2) \: we \: get \: \\ ⇒2x + y = 0⟶2 \times 1 + y = 0 \\ ⇒y = - 2 \\ \\ ∴ \: x = 1 \\ y = - 2$