I think that's the element on the second row and the first column which is 15.
Step-by-step explanation:

You have to find a common denominator 1st then add. So 16 is the common denominator the problem should be 2 7/16+1 14/16+8-16= 3 29/16 then you need to divide 29/16 you will have 4 13/16
Answer:
1.7(12) + 3(-6) = 84 - 18 = 66
Answer:
Lines BC and F represent perpendicular lines
Step-by-step explanation:
we have
<em>Line BC</em>

the slope of the line BC is 
<em>Line F</em>

the slope of the line F is 
we know that
If two lines are perpendicular, then the product of their slopes is equal to -1
so

we have
-----> slope line BC
-----> slope line F
Find the product of their slopes

therefore
Lines BC and F represent perpendicular lines