Question

The equation of a function is y= 10- 9x. Find the value of x when y= - 8​

Answer 1

`\red{x = 2}`

Explanation:

Given that,

y = 10 - 9x

Now we have to find the value of x when y is -8.

For that, you have to replace y with -8.

Let us solve it now.

`\rightarrow \: y = 10 - 9x \\ \rightarrow \: - 8 = 10 - 9x`

Make x the subject in the equation to find the value of x.

`\rightarrow - 8 - 10 = - 9x \\ \rightarrow - 18 = - 9x \: \: \: \: \: \: \: \: \\ \rightarrow ( - 18)/( - 9) = ( - 9x)/( - 9) \: \: \: \: \: \\ \rightarrow 2 = x \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:`

Answer 2

2 =x

Explanation:

y= 10- 9x

Find x

Let y = -8

-8 = 10 -9x

Subtract 10

-8 - 10 = 10 -9x -10

-18 = -9x

Divide each side by -9

-18/-9 = -9x/-9

2 =x