Answer:
81 pencils
Step-by-step explanation:
1. Set up variables
Pencils = p
notebooks= n
2. Set up a system of equations
p+n= 135 (The amount of supplies bought)
1.75n +0.35p = 122.85 (Equation for the cost)
3. Solve the system of equations (I'll use substitution)
a)p= 135-n (I just rearranged it)
1.75n + 0.35p= 122.85
b) Substitute the first equation into the second)
1.75n + 0.35(135-n) = 122.85
c) Solve!
1.75n + 47.25 - 0.35n = 122.85
1.4n = 75.6
n= 54
Serena bought 54 notebooks!
4. Substitute the number of notebooks into the first equation
p +n = 135
p + 54= 135
p = 81
Serena bought 81 pencils!!!
I hope this helps!!!!
Answer:
10.
Step-by-step explanation:
I am assuming that z is a whole number.
160z = x^2
z = x^2/ 160.
160 = 2*2*2*2*2*5
To make this a perfect square we multiply by 2 * 5
- this gives us 1600.
z = 1600/160 = 10.
Answer:
Halogen
Step-by-step explanation:
Halogen is a little more efficent but not as efficient as LED lighting.
Answer:
210.82
Step-by-step explanation:
arc length= 2pi r (Ø/360)
= 2x 3.14 x 47(257/360)=210.82
Answer:
The system consists of parallel lines, and the both lines have the same slope.
Step-by-step explanation:
The slope is the coefficient of x. (The coefficient of y should be 1)
When the slopes are equal, it means they are parallel.
