Find the line perpendicular to x=-7 through point (5,6)

The price of an item has been reduced by 30%. the original price was $30. what is the price of the item now ?

The scatterplot below shows the number of hours that students read weekly and the number of hours that they spend on chores weekly. which statement about the scatterplot is true?

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'