This is geometry. Please help explain this.

Which shows how to solve the equation 3/4x=6 for x in one step?

6. sarah saved $12.75 every week for a number of weeks, w. she received an additional $25 during the last week in which she saved money. write and solve an equation to find the number of weeks, w, for which sarah had saved money if she has $114.25 now.

Perform the indicated operation and write the answer in the form a + bi. (-5 + 2) + (3 - 6i)