Question

3x – 4y = 10

2x - 4y = 6
If (x, y) satisfies the system of equations above, what is the value of y?

Answer 1

y=1/2

Explanation:

3x-4y=10..............{1]

2x-4y=6................(2)

subtract equa(2) from equa(1)

x=4

substitute x=4 into equa(1)

3(4)-4y=10

12-4y=10

-4y=10-12

-4y=-2

y=1/2

Answer 2

`y=(1)/(2)`

Explanation:

We can solve this system using elimination.

In this case, we can eliminate y by subtracting both equations...

`3x-2x-4y-(-4y)=10-6\\x-4y+4y=10-6\\x=4`

Then, substitute 4 for x to solve for y...

`3x-4y=10\\3(4)-4y=10\\12-4y=10\\\text{Subtract 12 from both sides}\\-4y=-2\\\text{Divide both sides by -4}\\y=(1)/(2)`