1) x \ = \ 10, y \ = \ 5, \ -5(4x \ - \ 2y \ - \ 10) = \ \color{red}{ -5(4 \times 10 \ - \ 2 \ \times \ 5 \ - \ 10) \ = \ -100}
2) x \ = \ 17, y \ = \ 2, \ -2(2x \ - \ 3y \ - \ 17) = \ \color{red}{ -2(2 \times 17 \ - \ 3 \ \times \ 2 \ - \ 17) \ = \ -22}
3) x \ = \ 4, y \ = \ 5, \ 2x \ + \ \frac{15}{y} \ - \ 4 = \ \color{red}{2 \times 4 \ + \ \frac{15}{5} \ - \ 4 \ = \ 7}
4) x \ = \ 2, y \ = \ 3, \ 4x \ + \ 6y \ - \ 2 = \ \color{red}{4 \times 2 \ + \ 6 \ \times \ 3 \ - \ 2 \ = \ 24}
5) x \ = \ 8, y \ = \ 4, \ 4(3x \ - \ 3y \ + \ 8) = \ \color{red}{ 4(3 \times 8 \ - \ 3 \ \times \ 4 \ + \ 8) \ = \ 80}
6) x \ = \ 9, y \ = \ 7, \ 4x \ + \ 36y \ - \ 9 = \ \color{red}{4 \times 9 \ + \ 36 \ \times \ 7 \ - \ 9 \ = \ 279}
7) x \ = \ 6, y \ = \ 3, \ 2x(2y \ - \ 6) = \ \color{red}{ (2 \times 6)(2 \times 3 \ - \ 6) \ = \ 0}
8) x \ = \ 15, y \ = \ 4, \ 4(4x \ - \ 3y \ + \ 15) = \ \color{red}{ 4(4 \times 15 \ - \ 3 \ \times \ 4 \ + \ 15) \ = \ 252}
9) x \ = \ 19, y \ = \ 4, \ 2x \ + \ \frac{12}{y} \ - \ 19 = \ \color{red}{2 \times 19 \ + \ \frac{12}{4} \ - \ 19 \ = \ 22}
10) x \ = \ 2, y \ = \ 2, \ -2(4x \ - \ 4y \ - \ 2) = \ \color{red}{ -2(4 \times 2 \ - \ 4 \ \times \ 2 \ - \ 2) \ = \ 4}