the 43rd term of an arithmetic sequence is -671 and the 52nd term is -806. find the first term and the common difference.

First term = -41.

Common difference = -15.

Step-by-step explanation:

nth term: an = a1 + (n - 1)d  where a = first term and d = the common difference.

-671 = a1 + (43 - 1)d

-806 = a1 +(52 - 1)d

-671  = a1 + 42d

-806 = a1 + 51d

Subtracting ( to eliminate a1):

-671 - (-806) = 42d - 51d

-9d =  135

d = -15

Substitute for d in the first equation:

-671 = a1 + 42*-15

-671 = a1 - 630

a1 = -671 + 630 = -41.

2

step-by-step explanation:

when rotating a figure 180 degrees, imagine that you are able to take the figure and turn it clockwise or counterclockwise around a center point. to rotate a figure 180 degrees, you will need to apply the rule (x, y) → (-x, -y). start by using a coordinate grid with coordinates for each vertex of the figure. the center point of the coordinate grid is located at (0, 0), which is what you will rotate the figure around. write down the original coordinates of the shape you are going to rotate. then, apply the rule. for example, coordinate (1, 2) becomes (-1, -2). another example would be, coordinate (-4, -2) becoming (4, 2). after you change each original coordinate to the rotated coordinate, you will draw your new figure.

step-by-step explanation: