(! ) the formula to find a certain number in an arithmetic sequence is an=a1+d(n−1) where an represents the nth term of the sequence, a1 is the first term of the sequence, and d is the common difference. solve for d.

The correct option is A)

Step-by-step explanation:

Consider the provide equation.

We need to solve the equation for d.

Subtract from both sides

Divide both sides by n-1.

Hence, the correct option is A)

a net is a diagram that shows a “flattened” view of a solid. in a net, each face and base is shown with all of its dimensions. a net can also serve as a pattern to build a three-dimensional solid.

a pyramid is a three-dimensional object with a base that is a polygon and triangular faces that meet at one vertex.

" the net of a triangular pyramid consists of four triangles. the base here we are given of the pyramid is a equilateral   triangle, and the lateral faces are also triangles "

were is the equation