What is the result for M+X=?

Find the solution of this system of equation -7x+y=-20 9x-3y=36

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap

The table below shows the function f. determine the value of f(3) that will lead to an average rate of change of 19 over the interval [3, 5]. a. 32 b. -32 c. 25 d. -25