Answer:
x= 4 or <
Step-by-step explanation:
Answer:
26
Step-by-step explanation:
[(7+3)5-4]/2+3
-To solve this equation you have to use PEMDAS
P- Parentheses
E- Exponents
M- Multiplication
D- Division
A- Addition
S- Subtraction-
- With MD and AS you work left to right of the equation since they are in the same spot. (PE[MD][AS])
Step 1) [(10)5-4]/2+3
- First you do "P," parentheses, so you add 7+3=10
Step 2) [50-4]/2+3
- Next you do "M," multiplication, and multiply 10x5=50
Step 3) [46]/2+3
- Then you do "S," subtraction, and subtract 50-4=46
(FYI: Steps 1-3 were still in the parentheses. We had to start with the parentheses in the parentheses, work PEMDAS, and now we are out of the parentheses and have to work PEMDAS on the rest of the problem.)
Step 4) 23+3
- Now we do "D," division, and divide 46/2=23
Step 5) 23+3=6
- Finally we do "A," addition, and add 23+3=26 so the answer is 26
(FYI: "/" means division)
Answer:
x=2
y = 0
Step-by-step explanation:
3x + y = 6 -------------(i)
5x - 2y = 10 -------------(ii)
Multiply (i) by 2 ===> 6x +2y = 12
(ii) ===> <u> 5x - 2y = 10</u>
add ============> 11x = 22
x = 22/11
x = 2
Substitute x = 2 in (i)
3*2 + y = 6
6 + y = 6
y = 6 - 6
y = 0
4a + 3 = 11...subtract 3 from both sides
4a + 3 - 3 = 11 - 3...simplify
4a = 8 ....divide both sides by 4
(4/4)a = 8/4...simplify
1a, or just a = 2 <==
We want to see how long will take a healthy adult to reduce the caffeine in his body to a 60%. We will find that the answer is 3.55 hours.
We know that the half-life of caffeine is 4.8 hours, this means that for a given initial quantity of coffee A, after 4.8 hours that quantity reduces to A/2.
So we can define the proportion of coffee that Jeremiah has in his body as:
P(t) = 1*e^{k*t}
Such that:
P(4.8 h) = 0.5 = 1*e^{k*4.8}
Then, if we apply the natural logarithm we get:
Ln(0.5) = Ln(e^{k*4.8})
Ln(0.5) = k*4.8
Ln(0.5)/4.8 = k = -0.144
Then the equation is:
P(t) = 1*e^{-0.144*t}
Now we want to find the time such that the caffeine in his body is the 60% of what he drank that morning, then we must solve:
P(t) = 0.6 = 1*e^{-0.144*t}
Again, we use the natural logarithm:
Ln(0.6) = Ln(e^{-0.144*t})
Ln(0.6) = -0.144*t
Ln(0.6)/-0.144 = t = 3.55
So after 3.55 hours only the 60% of the coffee that he drank that morning will still be in his body.
If you want to learn more, you can read:
brainly.com/question/19599469
