I cannot evaluate this expression using the order of operations I know of, can someone explain it for me?

[Bones]

[math]b-y(y^4-b)-7[/math][math](y=2,b=7)[/math]
My work:
[math]7-2(2^4-7)-7[/math][math]7-2(16-7)-7[/math][math]7-2(9)-7[/math][math]7-18-7[/math][math]-11-7[/math][math]-18[/math]
Worksheet's Answer:
[math]38[/math]

 

[Otis]

Worksheet's Answer: 38

Hi Bones. You did good. The worksheet's answer is not correct.
[imath]\;[/imath]

 

[blamocur]

You'd get 38 for [imath](b-y)(y^4-b)-7[/imath].

 

[Dr.Peterson]

You'd get 38 for [imath](b-y)(y^4-b)-7[/imath].

... which is a mistake beginners often make! Good for you.

 

[Bones]

Oh okay. Thanks guys