Answer:
B. 165 degree angle
Step-by-step explanation:
There will be a 25 grams left after 3240 years.
The half-life of Radium-226 is 1620 years. If we divide 3240 by 1620 the answer is 2. So that means the amount of Radium-226 will divide in half twice.
100 / 2 = 50 / 2 = 25
5x-2+3x=17+12x-23 combine like terms
8x-2=12x-6
-8x -8x
-2=4x-6
+6 +6
4=4x divide each side by 4
x=1