7. 12*5/2=30in^2 (greater than 15 square inches) 8.5*4/2=10in^2 (less than 15in^2) 9.14*5/2=35in^2 (greater than 15in^2) 10. I have no clue on this one, sorry. 11. 20*7/2=70in^2 (greater than 15in^2) (I think) 12. 12^2-4^2=144-16=128 (that will be 8√2) And find the Areas A=4*8√2/2=16√2 And then find the area of the small triangle. A=4*(8√2-8)/2=(32√2-32)/2=16√2-16 Now minus the area of small triangle area from the big triangle area. 16√2-(16√2-16)=16√2-16√2+16=16in^2 (greater than 15in^2) So the Numbers that is greater than 15in^2 are 7,9,11,12
