Answer:
a) x=5
b) x=6
Step-by-step explanation:
a)
3x+7=180-(10x-22)
3x+7=202-10x
13x=195
x=5
b)
11x-3=4x+39
7x=42
x=6
I am so sorry I forgot what the formula names are but these are the correct solutions. It has been a while since I've done Geometry.
In between 194, and 195, but closer to 195
Commutative property
a+b=b+a
D
Answer: (1,-6)
Step-by-step explanation:
We rewrite the equation:
y = y0 * e ^ (- 0.0002 * t)
In this equation:
I = represents the initial amount of the isotope
We have then:
89% of the isotope left:
0.89 * y0 = y0 * e ^ (- 0.0002 * t)
We clear the time:
e ^ (- 0.0002 * t) = 0.89
Ln (e ^ (- 0.0002 * t)) = Ln (0.89)
-0.0002 * t = Ln (0.89)
t = Ln (0.89) / (- 0.0002)
t = 582.6690813
round to the nearest year:
t = 583 years
Answer:
There will be 89% of the isotope left in about:
t = 583 years