Which ratio represents cos x in the triangle to the right ?

Rose drew a regression line for this paired data set. her line passed through (1, 2) and (3, 5) . what is the equation of rose's regression line?

Last one and the bottom answer choice is y=(x-4)^2+1 you guys!

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)