Answer:
Either d or b and b looks like it works hte best
Step-by-step explanation:
To solve an equation for one variable, we will utilize PEMDAS ( parentheses, exponents, multiplication/division, add/subtract) but backwards. So we will first add/subtract any numbers to the other side to get the variable by itself. We will then divide/multiply any numbers to get the variable by itself.
14^2 - 9^2 = a^2
Easy enough
14^2 = 196
9^2 = 81
196 - 81 = 115
The square root of 115 = 10.72
The third side is 10.72km