i need some help D: this is the question 4x>12 (basically a one step equation) but i need to find what x is and i really need some help with an explanation on how to do these types of problems pelase explain :'(

65 8 7 4 5 6 8 4 3 2 1 9 5 6 4 2 1 6 5 1 5 1 3 2 3 5 multiply the third number in the first row by the seventh number in the third row. add this result to the fifth number in the second row. add to this total ten times the fourth number in the third row. subtract the eighth number in the first row from the result.

List x1, x2, x3, x4 where xi is the midpoint endpoint of the five equal intervals used to estimate the area under the curve of f(x) between x = 0 and x = 10.

Car a and car b were in a race .the driver of car b claimed that his car was twice as fast as car a