Answer:
10
Step-by-step explanation:
Answer:

Step-by-step explanation:
A regular polygon is a shape with equal sides and angles. Because of this, we can write the following equation to set two sides equal to each other:

Solving, we will get a in terms of b:

Now we can substitute a for (b+3) into our equation:

Therefore, the length of each side of this polygon is
.
Since the perimeter of the polygon consists of all five sides, the perimeter is:

Answer:
30 grams
Step-by-step explanation:
half life is 60 days so every 60 days the amount 480 grams will be half
in 240 days will decay 240 /60 = 4 times
once 480 /2 = 240
twice 240 /2 = 120
trice 120 / 2 = 60
four times 60/2 = 30 grams will be left
Answer:
The formula of area is Pi×R×R
and then you add all sides and answer of your question is 30cm
Answer:
6. 6x-21=33+9x 7. -15x=-5(3x+7) 8. 16x-19=113-6x 9. -19x-34=56-x 10. -6(4x+3)=6(4x-3)?
6. 6x-21 = 33 +9x
+21 + 21
6x = 54 + 9x
-9x -9x
-3x = 54
/3 /3
x = -18
7. -15x = -5(3x+7)
First multiply the -5 to the other numbers.
-15x = -15x - 35
0x = -35
7 is impossible I believe.
8. 16x-19 = 113-6x
+6 +6
22x - 19 = 113
+ 19 +19
22x = 132
/22 /22
x = 6
9. -19x - 34 = 56 - x
+19x +19x
-34 = 56 + 18x
-56 -56
-90 = 18x
/18 /18
x = -5
10. -6(4x+3) = 6[4x-3]
-24x - 18 = 24x - 18
+18 +18
-24x= 24x
x = 0, since only zero can make the equation true.