Hi please help me with 6 and 7 also 8 for brainlst :)

How to determine whether two known pairs of points are on the same line.

The triangles are similar. what is the value of x? show your work.

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!