Question

10. 2x + 7y = 1 2x - 4y = 12 Solve for y

Answer 1

Answer:

The solution for y = -1.

Step-by-step explanation:

Given:

$2x\ +\ 7y\ =\ 1$    ....(1)

$2x\ -\ 4y\ =\ 12$  ....(2)

So, to solve for y, first we solve for x in equation (2):

$2x-4y=12$

⇒$2x=12+4y$

Dividing both sides by 2,

⇒$x=6+2y$            

Now, substituting the value of x  in equation (1):

$2x+7y=1$

⇒$2(6+2y)+7y=1$

⇒$12+4y+7y=1$

⇒$12+11y=1$

⇒$11y=1-12$

⇒$11y=-11$

Dividing both sides by 11,

⇒$y=-1$

Therefore, the solution for y = -1.