Well okay first you want to write the expression.
6c²-5d+8 (next you replace the c with 5 and d with 4)
6(5)²-5(4)+8 (now you want to go left to right, first you want to do 5²)
6(25)-5(4)+8 (like always left to right :D ** 6 × 25**)
150-5(4)+8 (5 × 4, then 150· 5×4 )
150-20+8
130+8 (Now you add :D )
138
Final answer is 138
I hope I helped you out! :D
