Knowing that x varies directly with y, we know the basic skeleton of the equation is
y = mx.
To find
m, plug in the known coordinate
(8,10), where the
x-coordinate is
8 and the
y-coordinate is
10.

Then, plug in m to the equation to get
y = (5/4)x.
Finally, plug in the y-coordinate
18 to the equation and solve for x!

Your exact answer is
x = 72/5. However, if your teacher prefers decimals, then
x = 14.4Hope this helps!
Y= 1/2x +4
hopes this helps!
The value of x is
-4x + 8 = 42
-4x = 42 -8
-4x = 34
x = -8,5