we know that
The formula to calculate the slope between two points is equal to

we have

Step 1
<u>Find the slope GH</u>

substitute in the formula



Step 2
<u>Find the slope HJ</u>

substitute in the formula



Step 3
<u>Find the slope JG</u>

substitute in the formula



Step 4
Verify if triangle GHJ is a right triangle
we know that
if two lines are perpendicular, then the product of their slopes is equal to minus one
so

compare slope GH with slope JG
we have


-----> side GH and side JG are perpendicular
The triangle GHJ is a right triangle
The answer in the attached figure