Using the dot product:
For any vector x, we have
||x|| = √(x • x)
This means that
||w|| = √(w • w)
… = √((u + z) • (u + z))
… = √((u • u) + (u • z) + (z • u) + (z • z))
… = √(||u||² + 2 (u • z) + ||z||²)
We have
u = ⟨2, 12⟩ ⇒ ||u|| = √(2² + 12²) = 2√37
z = ⟨-7, 5⟩ ⇒ ||z|| = √((-7)² + 5²) = √74
u • z = ⟨2, 12⟩ • ⟨-7, 5⟩ = -14 + 60 = 46
and so
||w|| = √((2√37)² + 2•46 + (√74)²)
… = √(4•37 + 2•46 + 74)
… = √314 ≈ 17.720
Alternatively, without mentioning the dot product,
w = u + z = ⟨2, 12⟩ + ⟨-7, 5⟩ = ⟨-5, 17⟩
and so
||w|| = √((-5)² + 17²) = √314 ≈ 17.720
Hello!
Question 1
We first have to convert everything to yards since the concrete is charged by the cubic yards
15 feet = 5 yards
15 feet = 5 yards
3 inches = 0.08333
Multiply these to find the volume
5 * 5 * 0.08333 = 2.08325
Multiply this by the cost
2.08325 * 46 = 95.83
The answer is C) $95.83
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Question 2
You have to find the volume of the first pyramid
The equation we use is

V is volume
l is length
w is width
h is height
Put in the values we know

Multiply

Divide
V = 2389.3333
Now we use this to find the side length of the second pyramid

Multiply both sides by 3
<span>7167.999 = lw * 112
</span>
Divide both sides by 112
63.9999 = lw
Since it is a square pyramid we know that sides are equal
63.999 = l^2
Take the square root of both sides
8 = l
The answer is B) 8in
Hope this helps!
It would take her 12 minutes because if you mutipy 2/3 by 3/2 then you get 1 (as in one mile) and then you have to do that to the other side too so then you multiply 8 by 2/3 and get 12
Answer:

Step-by-step explanation:
<u><em>The picture of the question in the attached figure</em></u>
we know that
In the right triangle ABC
----> by SOH (opposite side divided by the hypotenuse)
substitute the given values

