Question

The point (x, -2/5) lies on the graph of . The value of x is

Answer 1

Basically, all it's asking is solve the equation for x, and plug in the y-value which is given (-2/5) and find the value of x. 

So, let's find out the equation for x:
$y = \frac{4-2x}{5}$
$5y = 4-2x$
$5y-4 = -2x$
$\frac{5y-4}{-2} = x$

Now, we have an expression, we can just plug in the y-value given to us and solve for x:
$\frac{5y-4}{-2} = x$
$\frac{5( \frac{-2}{5}) -4}{-2} = x$

Notice that the 5s cancel out and you are left with:
$\frac{-2 -4}{-2} = x$
$\frac{-6}{-2} = x$
$x = 3$

So, the x-value is 3!