Question

please solve 2 and explain

Answer 1

Given two equations. = x -2y = 0 ---------(1)
3x + 4y = 20 ---------(2)

EQ (1) × 2 => 2x - 4y = 0.
EQ (2) × 1 => 3x + 4y = 20.
____________
5x = 20
____________

x = 20/5 = 4.

Substituting x = 4 in eq (1) we get,

4 - 2y = 0

2y = 4

y = 4/2

y = 2.

(x,y) = (4,2).

So option (2).

:)