Answer:
x = 0
Explanation:
The critical information we need to know here is that:
"the product of the slopes of 2 lines that are perpendicular is -1"
So we need to find the slope of each and multiply them and equate it to -1 and solve for x. First, we need to find the slope.
Slope is given by the formula:

Where
x_1 and x_2 are the x coordinates of the points respectively, and
y_1 and y_2 are the y coordinates of the points respectively.
First, the slope of (3,4) and (8,-6) using formula above:

Secondly, the expression for slope of (2,4) and (x,3) using same formula:

Now we multiply both and equate to -1 and solve for x:

Thus, the value of x is 0