Answer:
The number of nickels is 45 and the number of dimes is 72.
Step-by-step explanation:
Let
x ----> number of nickels
y ----> number of dimes
Remember that
![1\ nickel=\$0.05](https://tex.z-dn.net/?f=1%5C%20nickel%3D%5C%240.05)
![1\ dime=\$0.10](https://tex.z-dn.net/?f=1%5C%20dime%3D%5C%240.10)
so
------> equation A
![0.05x+0.10(2y)=16.65](https://tex.z-dn.net/?f=0.05x%2B0.10%282y%29%3D16.65)
------> equation B
<em>Solve the system by substitution</em>
we have
------> equation A
------> equation B
Multiply both equations by 100 both sides
---->
--> equation C
----> equation D
substitute equation C in equation D
![(945-10y)+20y=1,665](https://tex.z-dn.net/?f=%28945-10y%29%2B20y%3D1%2C665)
solve for y
![945+10y=1,665](https://tex.z-dn.net/?f=945%2B10y%3D1%2C665)
![10y=1,665-945](https://tex.z-dn.net/?f=10y%3D1%2C665-945)
![10y=720](https://tex.z-dn.net/?f=10y%3D720)
![y=72\ dimes](https://tex.z-dn.net/?f=y%3D72%5C%20dimes)
Find the value of x
![5x=945-10y](https://tex.z-dn.net/?f=5x%3D945-10y)
![5x=945-10(72)](https://tex.z-dn.net/?f=5x%3D945-10%2872%29)
![5x=225](https://tex.z-dn.net/?f=5x%3D225)
![x=45\ nickels](https://tex.z-dn.net/?f=x%3D45%5C%20nickels)
<em>Alternative Method</em>
Solve the system by graphing
Remember that the solution is the intersection point both graphs
using a graphing tool
the solution is the point (45,72)
therefore
The number of nickels is 45 and the number of dimes is 72.
12rocks 6 in each 2 equal piles
4 in each 3 equal piles And 3 in each 4 equal piles
Answer:
105.
Step-by-step explanation:
21+21+21+21+21=105.
Answer:
The answer to your question is below
Step-by-step explanation:
pH definition
pH = - log [H⁺]
a) For pH = 2.4, solution A
2.4 = -log[H⁺]
[H⁺] = antilog⁻².⁴
[H⁺] = 0.00398
For pH = 9.4, solution B
[H⁺] = antilog⁻⁹.⁴
[H⁺] = 3.98 x 10⁻¹⁰
b) Divide hydrogen-ion concentration of solution A by hydrogen-ion concentration of solution B.
0.00398 / 3.98 x 10⁻¹⁰
10000000 times
c) By 7, because 7 is the number of zeros
Answer:
Step-by-step explanation:
3(x + 4) - 5 = 2x + 4
solve for x
x = -3