<span>Simplifying
2x + -3 = -1x + 3
Reorder the terms:
-3 + 2x = -1x + 3
Reorder the terms:
-3 + 2x = 3 + -1x
Solving
-3 + 2x = 3 + -1x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add 'x' to each side of the equation.
-3 + 2x + x = 3 + -1x + x
Combine like terms: 2x + x = 3x
-3 + 3x = 3 + -1x + x
Combine like terms: -1x + x = 0
-3 + 3x = 3 + 0
-3 + 3x = 3
Add '3' to each side of the equation.
-3 + 3 + 3x = 3 + 3
Combine like terms: -3 + 3 = 0
0 + 3x = 3 + 3
3x = 3 + 3
Combine like terms: 3 + 3 = 6
3x = 6
Divide each side by '3'.
x = 2
Simplifying
x = 2
answer x=2
Hope I Helped:D</span>
Answer:
tbh I think its the middle one
Step-by-step explanation:
Answer:
The percentage rate of decay per year is of 3.25%.
The function showing the mass of the sample remaining after t is 
Step-by-step explanation:
Equation for decay of substance:
The equation that models the amount of a decaying substance after t years is given by:
In which A(0) is the initial amount and r is the decay rate, as a decimal.
Every 21 years, its mass decreases by half.
This means that 
. We use this to find r, the percentage rate of decay per year.
![\sqrt[21]{(1-r)^{21}} = \sqrt[21]{0.5}](https://tex.z-dn.net/?f=%5Csqrt%5B21%5D%7B%281-r%29%5E%7B21%7D%7D%20%3D%20%5Csqrt%5B21%5D%7B0.5%7D)
The percentage rate of decay per year is of 3.25%.
Given that the initial mass of a sample of Element X is 80 grams.
This means that 
The equation is:
The function showing the mass of the sample remaining after t is
