Answer:
11 + √65
Explanation:
The distance between A and C is 7 units; the distance between C and B is 4 units. 7 will be a and 4 will be b. The distance between A and B is c, because it is unknown.
The Pythagorean Theorem states a² + b² = c². So, if you plug in the values for a and b, you will get 7² + 4² = c² which equals 49 + 16 = c², which equals 65 = c²
Now you have 65 = c², and the only way you can solve for c is to find the square root of 65. Since 65 is not a perfect square number and therefore does not have a whole number square root, you can leave it as √65.
Now the values you have are 7, 4, and √65. Add those together and you get 11 + √65. :)