Prove cos(x+y)+cos(x-y)=2cosxcosy

Kareem purchased a leather jacket for $800 with his new credit card. He budgeted $50 a month to pay toward the debt. When he rea

barxatty [35]

Answer:

1080

Step-by-step explanation:

Firstly, if he is paying 50 per month, we need to know the number of months it would take him to finish paying the money. Hence that would be 800/50 = 16 months

Now we know there is a surcharge of 17.5 for each month he owes a balance. The total balance he is to pay is thus 16 * 17.5 = 280

The total cost of the jacket is thus 800 + 280 = 1080

6 0

3 years ago

Triangle Q M N is shown. The length of Q M is 18, the length of M N is 17, and the length of Q N is 20. Law of cosines: a2 = b2

kvasek [131]

Answer:

53°

Step-by-step explanation:

17² = 18² + 20² - 2(18)(20) cos Q

289 = 324 + 400 - 720 cos Q

289 = 724 - 720 cos Q

-435 = -720 cos Q

0.6042 = cos Q

$cos^{-1} (0.6042) = Q$

Q = 52.83

3 0

3 years ago

Do you know parallelogram WXYZ Parkway 270° around point W what will be the length of the image WZ

Lerok [7]

Answer:

5 units

Step-by-step explanation:

Even if there is a transformation, it is asking for the length.

Therefore the length of WZ is 5 units

7 0

2 years ago

Consider the equation and the relation “(x, y) R (0, 2)”, where R is read as “has distance 1 of”. For example, “(0, 3) R (0, 2)”

Leviafan [203]

Answer:

The equation determine a relation between x and y

x = ± $\sqrt{1-(y-2)^{2}}$

y = ± $\sqrt{1-x^{2}}+2$

The domain is 1 ≤ y ≤ 3

The domain is -1 ≤ x ≤ 1

The graphs of these two function are half circle with center (0 , 2)

All of the points on the circle that have distance 1 from point (0 , 2)

Step-by-step explanation:

* Lets explain how to solve the problem

- The equation x² + (y - 2)² and the relation "(x , y) R (0, 2)", where

R is read as "has distance 1 of"

- This relation can also be read as “the point (x, y) is on the circle

of radius 1 with center (0, 2)”

- “(x, y) satisfies this equation , if and only if, (x, y) R (0, 2)”

* Lets solve the problem

- The equation of a circle of center (h , k) and radius r is

(x - h)² + (y - k)² = r²

∵ The center of the circle is (0 , 2)

∴ h = 0 and k = 2

∵ The radius is 1

∴ r = 1

∴ The equation is ⇒ (x - 0)² + (y - 2)² = 1²

∴ The equation is ⇒ x² + (y - 2)² = 1

∵ A circle represents the graph of a relation

∴ The equation determine a relation between x and y

* Lets prove that x=g(y)

- To do that find x in terms of y by separate x in side and all other

in the other side

∵ x² + (y - 2)² = 1

- Subtract (y - 2)² from both sides

∴ x² = 1 - (y - 2)²

- Take square root for both sides

∴ x = ± $\sqrt{1-(y-2)^{2}}$

∴ x = g(y)

* Lets prove that y=h(x)

- To do that find y in terms of x by separate y in side and all other

in the other side

∵ x² + (y - 2)² = 1

- Subtract x² from both sides

∴ (y - 2)² = 1 - x²

- Take square root for both sides

∴ y - 2 = ± $\sqrt{1-x^{2}}$

- Add 2 for both sides

∴ y = ± $\sqrt{1-x^{2}}+2$

∴ y = h(x)

- In the function x = ± $\sqrt{1-(y-2)^{2}}$

∵ $\sqrt{1-(y-2)^{2}}$ ≥ 0

∴ 1 - (y - 2)² ≥ 0

- Add (y - 2)² to both sides

∴ 1 ≥ (y - 2)²

- Take √ for both sides

∴ 1 ≥ y - 2 ≥ -1

- Add 2 for both sides

∴ 3 ≥ y ≥ 1

∴ The domain is 1 ≤ y ≤ 3

- In the function y = ± $\sqrt{1-x^{2}}+2$

∵ $\sqrt{1-x^{2}}$ ≥ 0

∴ 1 - x² ≥ 0

- Add x² for both sides

∴ 1 ≥ x²

- Take √ for both sides

∴ 1 ≥ x ≥ -1

∴ The domain is -1 ≤ x ≤ 1

* The graphs of these two function are half circle with center (0 , 2)

* All of the points on the circle that have distance 1 from point (0 , 2)

8 0

3 years ago

What is the simplified form of each expression? 7x^–8 × 6x^3

klio [65]

7*6*x^-8*x^3
42x^-8+3 (bases same powers add)
42x^-5
1/42x^5
so the simplified form of 7x^-8*6x^3 is=1/42x^5

7 0

3 years ago