The slope-point form:

The formula of a slope:

We have the points (7, -8) and (-4, 6). Substitute:

Answer:
It's true
Step-by-step explanation:
I hope it helps you
The complete question in the attached figure
Part a)
we know that
ABC is a right triangle
∠ACB=45°
AC=hypotenuse------> 6√2 cm
sin 45=AB/AC-----> AB=AC*sin 45----> AB=6√2*√2/2----> AB=6 cm
the answer part a) isAB=6 cmPart b)
we know that
volume of the pyramid=(1/3)*Area of the base*height
area of the base=50 cm²
height=6 cm
so
volume of the pyramid=(1/3)*50*6----> 100 cm³
the answer part b) is 100 cm³