Explain how to do this i don’t get it!

The vector matrix [2/7] is dilated by a favor of 1.5 and then reflected across the x axis. if the resulting matrix is [a/b] then a= and b=

65 8 7 4 5 6 8 4 3 2 1 9 5 6 4 2 1 6 5 1 5 1 3 2 3 5 multiply the third number in the first row by the seventh number in the third row. add this result to the fifth number in the second row. add to this total ten times the fourth number in the third row. subtract the eighth number in the first row from the result.

In triangle opq right angled at p op=7cm, oq-pq=1 determine the values of sinq and cosq