You need to use the Pythagorean theory. a² + b² = c². So you would end up with 10²+10²=c². So, 10²=100, therefore you would end up with 200=c². In order to find the length of the hypotenuse, you need to find C. To do this, you need to undo the square and find the square root of 200 and C. So, you would get √200=√c² which would equal 14.1 inches. Then, if needed to check the answer, plug the 10,10,and 14.1 back into the a²+b²=c² and it should make the statement true.
Remove parentheses
2c - 4 + 5c + 11
Combine like terms
Answer: 7c + 7
15.75+15.75=31.50 you add the two 15.75's because there are two adults then you add the amount of the admission for the adults and the kid 31.50+8.25 and you get $39.75
An addition sign between 978 and 842 would make the equation true!