I will mark BRAINIEST!! 20 points

Answer:
224
Step-by-step explanation:
7x^2y x=4 y=2 right so just replace the letters with the numbers you got so it'll look like 7 4^2 4 then 4^2= 16 then just multiply it all together 7x8x2=224
edit: don't forget PEMDAS or whatever its called