Answer:
You sold 15 cookies and 12 muffins
Step-by-step explanation:
So you're given that 1 cookie is sold for $3 and 1 muffin is sold for $7
You're also given that in total you made $129, and sold 27 items
Let's make equations from that, letting c stand for amount of cookies and m for amount of muffins.
Now we can use the second equation to find m:
c + m = 27
m = 27 - c
Not we can substitute m into the first equation to find c:
3c + 7m = 129
3c + 7(27-c) = 129 [substitute m for (27-c)]
3c + 189 -7c = 129 [distribute 7 into (27-c)]
-4c + 189 = 129 [combine like terms]
-4c = -60 [subtract 189 from both sides]
c = 15 [divide both sides by -4]
Now we can substitute c into the second equation to find m:
c + m = 27
15 + m = 27
m = 12
a. carbon chloride
b. nitrogen monoxide
c. copper (II) carbonate
d. chloric acid
Simplify the sum'
Hi Nova
(4u³+6u²+7)+(6u³-2u+7)
= 4u³+6u²+7+6u³-2u+7
Combine like terms
( 4u³+6u³)+(6u²)+(-2u)+(7+7)
= 10u³+6u² -2u+14
There no like terms so you can not simplify the sum
I hope that's help and if you have questions please ask !
Answer:
x= 2
Step-by-step explanation:
Answer:
The length and width that maximize the area are:
W = 2*√8
L = 2*√8
Step-by-step explanation:
We want to find the largest area of a rectangle inscribed in a semicircle of radius 4.
Remember that the area of a rectangle of length L and width W, is:
A = L*W
You can see the image below to see how i will define the length and the width:
L = 2*x'
W = 2*y'
Where we have the relation:
4 = √(x'^2 + y'^2)
16 = x'^2 + y'^2
Now we can isolate one of the variables, for example, x'
16 - y'^2 = x^'2
√(16 - y'^2) = x'
Then we can write:
W = 2*y'
L = 2*√(16 - y'^2)
Then the area equation is:
A = 2*y'*2*√(16 - y'^2)
A = 4*y'*√(16 - y'^2)
If A > 1, like in our case, maximizing A is the same as maximizing A^2
Then if que square both sides:
A^2 = (4*y'*√(16 - y'^2))^2
= 16*(y'^2)*(16 - y'^2)
= 16*(y'^2)*16 - 16*y'^4
= 256*(y'^2) - 16*y'^4
Now we can define:
u = y'^2
then the equation that we want to maximize is:
f(u) = 256*u - 16*u^2
to find the maximum, we need to evaluate in the zero of the derivative:
f'(u) = 256 - 2*16*u = 0
u = -256/(-2*16) = 8
Then we have:
u = y'^2 = 8
solving for y'
y' = √8
And we know that:
x' = √(16 - y'^2) = √(16 - (√8)^2) = √8
And the dimensions was:
W = 2*y' = 2*√8
L = 2*y' = 2*√8
These are the dimensions that maximize the area.
-3 + y = 0