Answer:
Step-by-step explanation:
We can let b and c represent the cost of a book and the cost of a CD, respectively. Then the purchases can be described by ...
3b +7c = 79
5b +2c = 35
Using Cramer's rule to find the solution, we have ...
b = (7(35)-2(79))/(7(5) -2(3)) = 87/29 = 3
c = (79(5)-35(3))/29 = 290/29 = 10
The cost of each book was $3; the cost of each CD was $10.
_____
Cramer's rule tells you the solution to ...
ax +by = c
dx +ey = g
is ...
x = (bg -ec)/(bd -ea)
y = (cd -ga)/(bd -ea) . . . . same denominator
This solution is fully equivalent to using elimination or substitution to solve the problem. Using these formulas effectively "cuts to the chase" without all the intermediate steps. The cross-multiplying pattern of differences is not hard to memorize.
Answer:
Step-by-step explanation:
Let 'm' denotes the mass of helicopter, 'g' denotes the gravity and 'a' denotes the acceleration.
We know that
Put
So,
Also, as per Newton's second law,
Put
So,
We know that the lift force is the sum of the gravitational force and the force of motion.
Answer: 3x-x+2=4
Step-by-step explanation:i think i am correct
Answer:
3.75
Step-by-step explanation:
Divide 2.5 by 2 to find out what 1/3 would be, then multiply that by 3 to get your answer - 3.75 pounds of chicken are called for
Hopefully this helps- let me know if you have any questions