The Answer is −7 .Thanks !!
ANSWER

EXPLANATION
We want to write the point-slope form of the line that passes through (6, 1) and is perpendicular to a line with a slope of -3.
The slope of this line is negative reciprocal of -3.

The point-slope form is given by:

We substitute the point and the slope to get;

Answer:
A
Step-by-step explanation:
112 m³
the solid is a rectangular pyramid with volume (V)
V =
× area of base × height =
× (8 × 4.2 ) × 10 = 112 m³