Question

find the solution for the given equation by using elimination method:- 1. 3x+4y=5 and 5x-2y=-9
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Answer 1

Given system of equations,

$\sf 3x + 4y = 5 - - - - - (1) \\ \sf 5x - 2y = - 9 - - - - - (2)$

Multiplying equation (2) with 2, we get :

$\sf 10x - 4y = -18 - - - - - - (3)$

Adding equations (1) and (3), we get :

$\sf 10x - 4y + 3x + 4y=- 18 + 5 \\ \\ \longrightarrow \sf 13x =-13 \\ \\ \longrightarrow \boxed{ \boxed{\sf \: x = -1 }}$

Putting value of 'x' in equation (1), we get :

$\longrightarrow \sf 3 \times -1 + 4y = 5 \\ \\ \longrightarrow \sf 4y = 5 + 3 \\ \\ \longrightarrow \sf 4y = 8 \\ \\ \longrightarrow \boxed{ \boxed{ \sf y = 2}}$

Therefore, (x,y) = (-1,2).

Answer 2

Answer:

Given :-

Two equation :-

$\large \bf \: 3x + 4y = 5$

$\large \bf \: 5x - 2y = -9$

To Find :-

x and y

Solution :-

First multiply equation 2 by 2

$\sf \: 10x - 4y = -18(3)$

10x - 3y + 3x + 4y = -18 + 5

10x + 3x = -13

13x =- 13

x = -13/13

X = -1

Now,

Finding y

3(-1) + 4y = 5

3 × -1 + 4y = 5

3 + 4y = 5

4y = 5 + 3

4y = 8

Y = 2