V = lwh
3 = (30)(40)(h)
3 = (1200)(h)
<u> </u><u>3 </u><u> </u><u /> = <u>1200h</u>
1200 1200
1/400 = h
Here is your perfect answer
<u>Answer-</u>
<em>The coordinates of the orthocenter of △JKL is (-4, 8)</em>
<u>Solution-</u>
The orthocenter is the point where all three altitudes of the triangle intersect. An altitude is a line which passes through a vertex of the triangle and is perpendicular to the opposite side.
For a right angle triangle, the vertex at the right angle is the orthocentre of the triangle.
Here we are given the three vertices of the triangle are J(-4,-1), K(-4,8) and L(2,8)
If the triangle JKL satisfies Pythagoras Theorem, then triangle JKL will be a right angle triangle.
Applying distance formula we get,

As,




Therefore, the vertex at K (-4, 8) is the orthocentre.