Perfect square is
a²+2ab+b²
so just take the square root of the end ones and add then double to get middle term
A.
m+10=10m, doubled is 20m
nope
B.
m+5=5m, doubled is 10m, yep
C.
m+2√15=fancy thing that won't get to 36m
D.
m+12=12m, doubled is 24m, yep
B and D
Divide 132 by 16 to get 8.25 and you have to round up because you can’t fit 0.25 of people on a table.
Answer:
Answer d)
,
, and 
Step-by-step explanation:
Notice that there are basically two right angle triangles to examine: a smaller one in size on the right and a larger one on the left, and both share side "b".
So we proceed to find the value of "b" by noticing that it the side "opposite side to angle 60 degrees" in the triangle of the right (the one with hypotenuse = 10). So we can use the sine function to find its value:

where we use the fact that the sine of 60 degrees can be written as: 
We can also find the value of "d" in that same small triangle, using the cosine function of 60 degrees:

In order to find the value of side "a", we use the right angle triangle on the left, noticing that "a" s the hypotenuse of that triangle, and our (now known) side "b" is the opposite to the 30 degree angle. We use here the definition of sine of an angle as the quotient between the opposite side and the hypotenuse:

where we used the value of the sine function of 30 degrees as one half: 
Finally, we can find the value of the fourth unknown: "c", by using the cos of 30 degrees and the now known value of the hypotenuse in that left triangle:

Therefore, our answer agrees with the values shown in option d)
Answer:
The answer is a dilation with a scale factor less than 1 and then a reflection.
Step-by-step explanation:
Answer:
The fraction of tiles that will be the color of "sand" is 23/60
Step-by-step explanation:
we know that
The sum of the fractions of the tiles must be equal to 1
Let
x ----> the fraction of tiles that will be the color of "sand"
we have that

solve for x
Find the Least Common Multiple of denominators

Multiply both sides by 60

simplify


therefore
The fraction of tiles that will be the color of "sand" is 23/60