Answer:
1) 69.5
2) 678.6
Step-by-step explanation:
pi3^2=28.27*9=254.5 18*18=324-254.5=69.5
pi24^2=1809.6*.5=904.8 pi6^2=113.1*.5=56.55*4=226.2 904.8-226.2=678.6
Answer:
a. =11+ 1
b. =4x+ (-7y) + (-5z) +6
c. (-3x) + (-8y) +(-4)+(-8/7z)
Step-by-step explanation:
a. 20 - 9 + 8 -7
=11+ 1 ( this is obtained by solving)
b. 4x - 7y - 5z + 6
=4x+ (-7y) + (-5z) +6
We multiply the negative sign with the positive sign to get a minus so the answer remains the same and the expression is written as an addition sum.
c. -3x - 8y - 4 - 8/7z
-[ 3x+8y+4+8/7z]
or
(-3x) + (-8y) +(-4) +(-8/7z)
The minus sign is taken as common leaving the expression with the plus only.
It can be written in the same manner as above, adding the negative terms so that the expression is written as a sum.
The function that models exponential growth is:
P(t) = P0*(1 + r)^t, where
P0 = P(0) is the initial value of P
r is the growth rate as a decimal
In our case we have:
P(0) = 2800
r = 0.035 or 3.5%
P(t) = 2800*(1 + 0.035)^t
P(t) = 2800*(1.035)^t
The same exponential function written using y and t is:
y = 2800*1.035^t.
Explanation: https://softmath.com/algebra-word-problems/to-begin-a-bacteria-study-a-petri-dish-had-2800-bacteria
Answer:
20 nickels and 26 dimes
Step-by-step explanation:
- She has $3.60 in nickels and dimes
- a nickel is $0.05 and a dime is $0.10
- let n be the number of nickels and d be the number of dimes
- thus the first equation is 3.6 = 0.05n +0.1d
- If she has 46 coins then n + d = 46
- then n = 46 - d
- sub n = 46 - d into 3.6 = 0.05n +0.1d
- 3.6 = 0.05(46 - d) + 0.1d
- 3.6 = 2.3 -0.05d+0.1d
- 1.3 = 0.05d
- 26 = d
- sub d = 26 into n+d=46
- n+26=46
- n=20
- Check by subbing n=20 and d=26 into 0.05n +0.1d
- 0.05(20) +0.1(26)
- 1+2.6 = 3.6