Question

If x and y satisfy both 9x+2y=8 and 7x+2y=4, then y=?

Answer 1

Answer:

The value of y is -5

Step-by-step explanation:

we have

$9x+2y=8$ ------> equation A

$7x+2y=4$ ------> equation B

we know that

If x and y satisfy both equations, then (x,y) is the solution of the system of equations

Using a graphing tool

Remember that

The solution of the systems of equations is the intersection point both graphs

The intersection point is (2,-5)

therefore

The solution of the system of equations is the point (2,-5)

The value of y is -5