Solution Incorrect to Equation

[sunny123]

This is a copy paste from my math text book. I am getting answer as 11, while the book is showing as 25

My expansion is as follows
2(0-1)-1(8-1)+5(4-0)
2(-1)-1(7)+5(4)
-2-7+20 = 11

Please correct me if I am doing some mistake

 

[pka]

You missed the fact \(\displaystyle -(-1)=1,~2(0-1){\large\color{red}+}(8-1)+5(4-0)\)

 

[sunny123]

You missed the fact \(\displaystyle -(-1)=1,~2(0-1){\large\color{red}+}(8-1)+5(4-0)\)

hi, i think i may have got it. Thanx for help