f(x)=lnx
y=f(x)
dy/dx= 1/x
tangent at (x,y) has slope 1/x
eqn of tangent is y = mx + c
since the tangent passes through origin, c=0
substitute y = lnx and m= 1/x to above eqn
lnx = 1
x=e
y=lne=1
Answer: Time taken by Ximena to paint the fence alone = 24 hours
Time taken by Candice to paint the fence alone = 12 hours
Step-by-step explanation:
Let x= Time taken by Ximena to paint the fence alone .
Time taken by Candice to paint the fence alone = x-12
As per given , we have

if x= 4
Time taken by Ximena = 4 hours
Time taken by Candice = 4-12 hours =-8 hours which is not possible. (time cannot be negative)
Therefore, x= 24
Such that
Time taken by Ximena to paint the fence alone = 24 hours
Time taken by Candice to paint the fence alone = 24-12=12 hours
Answer:
$720
$360
Step-by-step explanation:
Let the cost of couch be A and that of coffee table be B
Given couch and coffee table cost $1080
That’s
A + B = $1080
Also, the cost of couch A is 2 times the cost of coffeee table B.
That’s
A = 2B
We now have two equations
A + B = 1080
A = 2B
Now ,substitute 2B for A in the first equation .
We have
A + B = 1080
2B + B = 1080
3B = 1080
Divide both sides by 3
3B/3 = 1080/3
B = 360
The coffee table cost $360
Remember A = 2B
Therefore
A = 2 x $360
A = $720
The couch cost $720 while the coffee table cost $360
Answer:
false
Step-by-step explanation:
x=4andy=7
2×4+7 isnot equal to 7