Answer:
f(x) = sec x. tan x
⇔ f(x) = 1/cosx . cosx/sinx
⇔ f(x) = sin x
+) when f(x) is increasing => sin x increases
=> x will increase
+) f(x) is decreasing => x will decrease
+) f(x) is concave up => x ∈ (-pi/2; 0)
+) f(x) concave down => x ∈ (0; pi/2)
Step-by-step explanation:
4- 20
I created an equation for this one:
4x+x=100
- 4x= four times the amount of the other number
- x= the number
- combine like terms
5x=100
x=20
5. One pretzel costs $3
Create an equation:
Mulitply 2s+p=7 by -2 so you can use elimination.
Combine equations
p=3
Answer:
(4, 9) and (-10, -8)
Step-by-step explanation:
Answer:
14 miles.
Step-by-step explanation:
Let the distance traveled from home to destination = x miles.
Speed while going to friend's house = 35 miles per hour.
Speed while coming back = 40 miles per hour.
Total Time taken for the journey = 45 minutes = 0.75 hours.
Let the time taken while going to friend's house = y hours.
Therefore, the time taken while going to friend's house = (0.75 - y) hours.
To find x and y, model the speeds of both the journeys.
Speed while going to friend's house = Distance/Time.
35 = x/y.
x = 35y (Equation 1).
Speed while coming back = Distance/Time.
40 = x/(0.75 - y).
x = 40(0.75 - y) (Equation 2).
Since x = x, therefore:
35y = 30 - 40y.
75y = 30.
y = 30/75.
y = 0.4 hours.
Put y = 0.4 hours in Equation 1:
x = 35y.
x = 35(0.4).
x = 14.
Therefore, the distance between my friend's house and my house is 14 miles!!!
141) d
121) c
23) c
51) a
49) c
