Which quadrilateral always has diagonals that are congruent but not necessarily perpendicular?

a) parallelogram
b) rectangle
c) rhombus
d) square

its a rectangle

Step-by-step explanation:

1) 1/2 * 1/2 = 1/4

2) 43/100 of mine were heads, and (.43)^2 = .1849

3) 1/2 * 1/2 = 1/4

4)57/100 of mine were tails, and (.57)^2 = .3249

5) 1/2 * 1/2 * 2 (multiply by 2 because order doesn't matter) = 1/2

6) .43 *.57 = .2451

7) There is probably a difference becasue there wasn't enough data. The more times you flip the coin, the closer you'd get to 1/2 head 1/2 tails (theoretically), but you can't flip a coin an infinite amount of times, so it (usually) will not give you an exact 1:1 ratio between heads and tails