A textbook store sold a combined total of 402 sociology and chemistry textbooks in a week. The number of sociology textbooks sold was two times the number of chemistry textbooks sold. How many textbooks of each type were sold?

a_n = a_1 + (n - 1)d

the first term is 6.

the common difference d = ?

when you find d, replace n with 7 and d with the common difference to find your answer.

8(1/6)

step-by-step explain:

49/6= 48

8 (1/6)

step-by-step explanation:

rectangles are made up of 4 right angles, which means that a side and a base meet perpendicular to one another.   their slopes then have to reflect perpendicular slopes.   perpendicular slopes are opposite reciprocals of one another.   for example, if the slope of one line is +2/3, then the perpendicular slope to that would be -3/2.   so we look for that combination in our choices.

all of them satisfy that condition (so what's the question, i guess? )