Question

2x+3y=9 and 3x+4y=5​

Answer 1

Step-by-step explanation:

We have,

2x+3y=9 ……. (1)

3x+4y=5 …… (2)

Now,

y=

3

9−2x

On putting the value of y, in equation (2), we get

3x+4(

3

9−2x

)=5

3x+

3

36−8x

=5

9x+36−8x=15

x=15−36

Now, put the value of x in equation (1), we get

y=

3

9−2(−21)

y=

3

9+42

y=

3

51

=17

Hence, this is the answer.

Answer 2

The given equations are

2x + 3y = 9 …(i)

and 3x + 4y = 5 …(ii)

Multiplying equation (i) by 3 and (ii) by 2 and then subtracting,

we get y = 17

Putting the value of y = 17 in equation (i),

we get 2x + 3 x 17 = 9

⇒ 2x + 51 = 9

⇒ 2x = 9 – 51

⇒ 2x = -42

⇒ x = -21

Hence the required solution is

x = -21 and y = 17