9514 1404 393
Answer:
after 7 minutes
19,600 feet
Step-by-step explanation:
Here's the "pencil and paper" solution:
The two altitude equations are ...
y = 41300 -3100x
y = 2800x
They can be solved by setting the expressions for y equal to each other.
2800x = 41300 -3100x
5900x = 41300
x = 41300/5900 = 7
y = 2800·7 = 19600
The planes will both be at 19,600 feet after 7 minutes.
An Acute angle
less than 90*= acute angle
18 - (8 - 3 • (2t + 5)) = 0
6t + 25 = 0
3.1 Solve : 6t+25 = 0
Subtract 25 from both sides of the equation :
6t = -25
Divide both sides of the equation by 6:
t = -25/6 = -4.167
Final answer is
t = -25/6 = -4.167
Answer: 20 oranges and 5 mangoes
Step-by-step explanation:
Define the following:
x = number of oranges
y = number of mangoes
Make the following system of equations:
x + y = 25
0.35x + 1.00y = 12.00
Solve for x:
y = 25 - x
⇒ 0.35x + 1.00(25 - x) = 12.00
⇒ 0.35x + 25 - x = 12.00
⇒ -0.65x = -13.00
⇒ x = 20
Solve for y:
20 + y = 25
y = 5
∴ 20 oranges and 5 mangoes were purchased.