Question

x-2y=4 and 4x-2y=-3 by elimination method​

Answer 1

Answer:

x= -7/3 and y= -19/6

Answer 2

$\large{\textsf{\underline{Given}}}$

• x -2y = 4
• 4x -2y = -3

$\large{\textsf{\underline{To find}}}$

• The value of x and y by Elimination Method.

$\large{\textsf{\underline{Solution}}}$

Let,

x -2y = 4 -----(1)

4x -2y = -3 ------(2)

Now we will multiply eq(1) by 4 to make the coefficient of x equal.

$4 \times (x - 2y = 4) \\ 1 \times (4x - 2y = - 3) \\ \\ \longrightarrow \: 4x -8y = 16 \\ \longrightarrow4x - 2y = - 3 \\ \: \: \: \: \: - \: \: \: \: \: \: \: + \: \: \: \: \: \: \: + \\ \\ \{ \text{changing signs} \} \\ \\ we \: get \\ \\ \: \: \: \cancel{4x} - 8y = 16 \\ - \cancel{ 4x} + 2y = \: \: 3 \\ \\ \implies \: - 6y = 19 \\ \\ \implies \boxed{ \red{y = - \frac{19}{6} }}$

Putting value of y in eq(1)

$\implies \: x - 2 \left ( - \frac{19}{6} \right) = 4 \\ \\ \implies \: x - \left( - \frac{19}{3} \right) = 4 \\ \\ \implies \: x + \frac{19}{3} = 4 \\ \\ \implies \: x = 4 - \frac{19}{3} \\ \\ \implies \: x = \frac{4(3) - 19}{3} \\ \\ \implies \: x = \frac{12 - 19}{3} \\ \\ \implies \boxed{ \red{x = - \frac{7}{3} }}$