Answer:
B : 
Step-by-step explanation:
If you divide a rhombus using its diagonals, you get 4 right triangles, whose legs are both 1/2 the length of the diagonals.
This means that the legs of one of those 4 triangles have lengths of 2x/2, and 8x/2, so the legs of one of those triangles x and 4x. This makes the length of one side equal to 
. Because all 4 sides are the same length, you multiply this value by 4, and get , which is B.
2.6 because you substract
2 + 7 - 9 + 11
= 9 - 9 + 11
= 0+ 11
= 11
hope it's helpful !
have a nice day :)
We write an inequality:
This equation cannot be solved using trivial methods found in high-school classes, so we resort to graphical examination.
is a linear function while
is an exponential one (with limit zero as
approaches
). We see that
at approximately
and
.
Indeed, using a computer algebra system such as the ones on modern TI calculators and on many internet sites gives equality at
. By observing our graph, we see that
when
or
.
