18 is the answer I believe hopefully this is correct
Answer:
The first picture presented showing to rows of dots in a somewhat straight line.
Step-by-step explanation:
Let the cost of 1 notebook be x and the cost of 1 binder be y.
4 notebooks and 3 binders would cost 23.5
Therefore, 4x + 3y = 23.5 (1)
7 notebooks and 6 binders would cost 44.5
Therefore, 7x + 6y = 44.5 (2)
Multiply the first equation by 2.
8x + 6y = 47 (3)
(3) - (2) gives
x = 2.5
Substitute the value of x in (1), we get,
4(2.5) + 3y = 23.5
10 + 3y = 23.5
3y = 23.5 - 10
3y = 13.5
y = 13.5/3
y = 4.5
Hence, cost of 5 notebooks and 3 binders is:
5x + 3y = 5(2.5) + 3(4.5)
= 12.5 + 13.5
= 26
Hence, cost of 5 notebooks and 3 binders is $26.
The derivative is the rate of change of a function, basically represents the slope at different points. To find the derivative of the given function you can use the power rule, which means, if n is a real number, d/dx(x^n)= nx^(n-1). This is a simplification of the chain rule based on the fact that d/dx(x)=1. Anyway, this means that d/dx(x^3 + 1)= 3x^2. Here n is 3 and so it is 3*x^(3-1)= 3x^2. The derivative of x^3+1 is 3x^2.
If you are wondering what happened to the 1, for any constant C, d/dx(C)=0.
Answer:
The area of ∆DEF = 4.5in²
Step-by-step explanation:
From the above diagram,
∆BAC ~∆DEF
It is important to note that if two triangles are similar, the ratio of their areas is equal or equivalent to the ratio of the areas of their sides
This means for the above question, that
We have the bigger triangle = ∆BAC has a side of 4 in and Area = 8 in²
The small triangle has a side of 3in
Finding the scale factor k = ratio of the sides of both Triangles
k = 4/3
k² = (4/3)²
k² = 16/9
Hence,
Area of ∆BAC/ Area of ∆DEF = 16/9
8in²/Area of ∆DEF = 16/9
We cross Multiply
8 in² × 9 = Area of ∆DEF × 16
Divide both sides by 16
Area of ∆DEF = 72/16
= 4.5in²
Therefore, the Area of ∆DEF rounded to the nearest tenth = 4.5in²