Answer:
126 sq units.
Explanation:
We want the side surface area only, we'll calculate both
For the sides, we have 4 triangles with a base of 7 and a height of 9 units.
The area of a triangle is calculated with A = (b * h)/2
So, each of the sides of the pyramid has an area of:
A = (7 * 9) / 2 = 31.5 sq units
There are four sides, so total lateral area: 4 * 31.5 = 126 sq units.
The total lateral area of that pyramid is 126 sq units.