Question

The value of x in this system of equations is 1.

3x + y = 9

y = –4x + 10

Substitute the value of y in the first equation:
Combine like terms:
Apply the subtraction property of equality:
Apply the division property of equality:
3x + (–4x + 10) = 9

–x + 10 = 9

–x = –1

x = 1

What is the value of y?

Answer 1

In my opinion the answer is y = 6

Explanation:

We have two unknowns from the equation therefore, two equations are needed. These equations are:

3x + y = 9

y = –4x +10

To solve for y, we first substitute the second equation to the first one.

3x + –4x +10= 9

x = 1

We substitute the value of x to either of the equations and solve for y.

y = –4(1) +10

y = 6

Answer 2

y=6

Explanation:

`3x + y = 9`

`y = -4x + 10`

Substitute the value of y in the first equation:

`3x + (-4x + 10) = 9`

Apply the subtraction property of equality:

`-x + 10 = 9`

`-x=-1`

x=1

Substitute 1 for x in the given y equation

`y = -4x + 10`

`y = -4(1)+ 10`

y=6