Simply plug the number after the semi colon into each question's respective variable.
1. Is k=-1 a solution to this problem? Is 9(-1)=10-(-1)? we see that -9=10+1=11 which is not a true equality. since -9 is not 11 then "No" is the correct answer to number 1.
3. 3(-10)÷(-6)=5-(-10) ? -30÷-6=5+10? 5=15? No, not true, thus "No" is the correct answer.
5. 8-8=2(8)-16? Is 0=16-16 ? Yes!
7. Is 2(7-2)-5(7)=5(2-7)? 2(5)-35=5(-5)? 10-35=-25 -25=-25 Bingo! Yes.