Answer:
30% constituents=20 mL
10% constituents=180 mL
Step-by-step explanation:
x= 30% volume
y=10% volume
For our first equation, we know the total volume is 200 mL and is the sum
x+y=200
y=200-x (1)
For our second equation, we do a mass balance for 200 mL of final solution.
12% w/v = 0.12 g/mL
This means that in 1 mL of solution, we have 0.12 g of NaCl.
For any solution, concentration multiplied by volume will give the mass of NaCl:
Mass in x mL= C*V (g/mL) (mL)
So in 200 mL, we have
0.12*200 (g/mL) (mL)
=24g of NaCl
Cx*Vx + Cy*Vy=24
0.3x+0.1y=24 (2)
Substitute y=200-x into (2)
0.3x+0.1(200-x)=24
0.3x+20-0.1x=24
0.2x=24-20
0.2x=4
Divide both sides by 0.2
0.2x/0.2=4/0.2
x=20
Substitute x=20 into (1)
y=200-x
y=200-20
y=180
30% constituents=20 mL
10% constituents=180 mL
Answer:
9
Step-by-step explanation:
7r+18=r²
r²-7r-18=0
factorizing
r²+2r-9r-18=0
r(r+2)-9(r+2=0
(r-9)(r+2)=0
r-9=0
r=9
check
(r²)=(9*9)=81
7r+18=7(9) + 8=81
Answer:
f(x) = 3 cos (2Pi / period value ; x )+ 2
or see answer using 2 as the period see answer in bold below.
Step-by-step explanation:
cosine function amplitude of 3 is A = 3
The period is used to find B
You need to show period value as the denominator and work out from there with 2PI as a function numerator to show as 2pi / period can be a data angle
C is the adding value.
Acos (Bx) + C
A = 3
Bx = 2 pi / period
C = + 2
However f 2 is also the period found
then we just plug in 2 to above formula
f(x) = 3 cos (2Pi / 2 ; x )+ 2
f(x) = 3cos (x pi) + 2
Answer:
Right Triangle, Acute Triangle, and Obtuse Triangle
Step-by-step explanation:
I can't draw it here but the right triangle has a side of 90°.
An acute triangle has a side smaller than 90°.
An obtuse triangle has a side bigger than 90°.
