Question

What is the value of y in the equation when x=3? Image below.

Answer 1

When, x=3, the value of y is 9

Explanation:

The given equation is;

`6.4x+2.8y=44.4`

Let us multiply through by 10 to get;

`64x+28y=444`

When x=3, we get;

`64(3)+28y=444`

`192+28y=444`

Group similar terms;

`28y=444-192`

`28y=252`

Divide both sides by 28

`y=(252)/(28)`

`y=9`

When x=3, y=9

Answer 2

9

Explanation:

We need to first plug in 3 into the place of "x" and then do some algebra and solve for the value of y. The steps are shown below:

`6.4x+2.8y=44.4\\6.4(3)+2.8y=44.4\\19.2+2.8y=44.4\\2.8y=44.4-19.2\\2.8y=25.2\\y=(25.2)/(2.8)\\y=9`

Hence, the value of y is 9