The half-life is defined to be the time it takes for any specified property, in this case, mass, to be half of its original value. Thus, given the equation:
N = No*e^-kt, with N = 9, No = 18, and k = 0.1226, the value of t, in days, can be determined. Solving the equation, the half-life of the substance, or the time it takes for the sample to be 9 grams is 5.7 days.
X=10-2y
x=5y-1
10-2y=5y-1
10=7y-1
11=7y
11/7=y
x=5(11/7)-1
x=55/7-1
x=48/7
Step-by-step explanation:
The average rate of change of a function f(x) over an interval [a, b] is:
(f(b) − f(a)) / (b − a)
(f(4) − f(0)) / (4 − 0)
(7/17 − -1/5) / 4
(52/85) / 4
13/85
Important:
The sum of the three angles inside
every triangle is always 180°.
First, look at the left triangle alone.
Two of its angles are 46° and 58° . (46° + 58° ) = 104°
That leaves (180° - 104° ) = 76° degrees for the third angle.
The third angle in that triangle is 'x'.
x = 76° .
At the point where 'x' and 'z' come together:
'x' and 'z' are a "linear pair".
Placed side-by-side, they form a straight line.
So (x + z) = 180° .
But x = 76°.
So z = (180° - 76°). z = 104° .
Now look at the the skinny triangle on the right alone.
The angle at the top is 13°, and z = 104°.
(13° + 104°) = 117° .
That leaves (180° - 117°) = 63° for the third angle.
'y' is the third angle.
y = 63° .