What is the length of EF in the right triangle below?

36

Step-by-step explanation:

use the Pythagorean theorem, which is a^2+b^2=c^2 where c is always the hypotenuse and a & b can be interchangeable because they are just the legs.

in this case the hyp is 39

so 39^2=15^2+EF^2

which can also be 39^2-15^2=ef^2

1521-225=ef^2

now square root both sides to get just ef

ef= square root of 1296

ef=36

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.