All categories

2 years ago

Find the angle between the vectors (9,-1 ) and (4,2). Carry your intermediate computations to at

Mathematics

1 answer:

nasty-shy [4]2 years ago

7 0

Answer:

33°

Step-by-step explanation:

(9 , -1), (4 , 2)

cos α = (x₁ * x₂ + y₁ * y₂) / (√(x₁² + y₁²) * √(x₂² + y₂²))

x₁ = 9,

x₂ = 4,

y₁ = -1,

y₂ = 2

cos α = (9*4 + -1*2) / (√(81+1) * √(16+4))

= 34/ (√82 * √20)

≈ 0.8396

α = 32.91° ≈ 33°

You might be interested in

Find the slope of the given points (6, -10) and (-15, 15). Show your work.

charle [14.2K]

Answer:

Step-by-step explanation:

The slope of a line between two points can be calculated by dividing the difference of y values by the difference of x values

in this case

$m = \frac{y_2-y_1}{x_2-x_1} = \frac{15-(-10)}{-15-6} = \frac{25}{-21} = \frac{-25}{21}$

6 0

3 years ago

Aleena expands 2xx+3-5(x-2) as 2x2+3-5x-10. Has she expanded it correctly? Please identify the mistakes and write the correct wa

Nimfa-mama [501]

The given expression is :

2xx+3-5(x-2)

We know that, $x{\cdot}x=x^2$

$=2x^2+3-5(x-2)\\\\=2x^2+3+(-5)(x)+(-5)(-2)\\\\=2x^2+3-5x+10$

Aleena expands 2xx+3-5(x-2) as 2x²+3-5x-10. She is mistaken because the sign before 10 should be +10 instead of -10. Hence, the correct expanded form is 2x²+3-5x+10. Hence, this is the required solution.

5 0

2 years ago

HELLLP ASAP FIRST PERSON WITH CORRECT ANSWER WILL RECEIVE BRAINLIEST

Nikitich [7]

Rotating Q 180 degrees using the center P has the same effect as reflecting Q over the Line M
Step-by-step explanation:
Rotating Q 180 degrees using the center P has the same effect as reflecting Q over the Line M and this is because Lines L and M are perpendicular lines ( i.e. lines that meet a right angle ( 90° ).
Hence rotating Q 180 degrees form the center will be similar to reflecting Q over any of the perpendicular lines

3 0

3 years ago

A water tank that holds 30 gallons of water when full is leaking 3/4 gallon of water every hour. If no one notices and stops the

viva [34]

It will take 40 hours for the water tank to become empty.

Explanation:
Divide 30 by 0.75 (equivalent to 3/4).

7 0

3 years ago

Please let me know what you guys think about this problem

Molodets [167]

Answer:

8.8%

Step-by-step explanation:

you have ( $150 / $1695 ) * 100 = 8.8

4 0

3 years ago