The expression represents commutative property of addition
Hope this helps
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The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years
Simplify brackets
351 = y * 8 + 7
Regroup terms
351 = 8y + 7
Subtract 7 from both sides
351 - 7 = 8y
Simplify 351 - 7 to 344
344 = 8y
Divide both sides by 8
344/8 = y
Simplify 344/8 to 43
43 = y
Switch sides
<u>y = 43</u>
Answer: cant really see the words and my laptop makes it really blurry already
Step-by-step explanation: