Lets x is price of noble fir trees and y - is price for douglas fir trees
students got 5x+3y=420$ on friday
and 12x+9y=1080
now we need just solve the system of equations
5x+3y=420 - multiply by 3
12x+9y=1080
15x+9y=1260
12x+9y=1080
substract second equation from first
15x-12x=1260-1080
3x=180
x=60$ - the price of noble fir trees
put value x=60 in first equation 5x+3y=420
5*60+3y=420
300+3y=420
3y=120
y=40$ - price of Douglas fir trees
Answer: Noble fir trees cost $60 and Douglas fir trees cost $40
Answer:
c
Step-by-step explanation:
X = 90-22
x = 68
..............
Answer:
g(0) > f(0)
Step-by-step explanation:
Evaluate the functions at the point of interest: x=0.
g(0) = 20·1.5^0 = 20·1 = 20
f(0) = -40 . . . . from the table
Since 20 > -40, we conclude ...
g(0) > f(0)
Answer:
n = 18 cycles
Step-by-step explanation:
To know how many times does the current oscillates in the given time, you take into account that the number of oscillation can be calculated by using the following expression:
(1)
f: frequency of the oscillation of the current
t: time = 0.30s
The frequency is the number of cycles per second, that is, f = 60 cycles/s
You replace the values of f and t in the equation (1):
In 0.30s the current oscillates 18 times