Answer:
1) 25%
2) $17.54
Step-by-step explanation:
1) The boots were reduced from $80 to $60, therefore the total amount they were reduced by in terms of money is $20. To find out what percentage $20 is of $80, you divide.
20/80 = 0.25
0.25 = 25 % (to change a decimal to a percentage, you multiply by 100)
2) 20% = 0.20 (to change a percentage to a decimal, you divide by 100)
To find 20% of $87.70, multiply 0.20 by 87.70.
87.70 x 0.20 = 17.54
Answer:
The solutions of the equation are 0 , π
Step-by-step explanation:
* Lets revise some trigonometric identities
- sin² Ф + cos² Ф = 1
- tan² Ф + 1 = sec² Ф
* Lets solve the equation
∵ tan² x sec² x + 2 sec² x - tan² x = 2
- Replace sec² x by tan² x + 1 in the equation
∴ tan² x (tan² x + 1) + 2(tan² x + 1) - tan² x = 2
∴ tan^4 x + tan² x + 2 tan² x + 2 - tan² x = 2 ⇒ add the like terms
∴ tan^4 x + 2 tan² x + 2 = 2 ⇒ subtract 2 from both sides
∴ tan^4 x + 2 tan² x = 0
- Factorize the binomial by taking tan² x as a common factor
∴ tan² x (tan² x + 2) = 0
∴ tan² x = 0
<em>OR</em>
∴ tan² x + 2 = 0
∵ 0 ≤ x < 2π
∵ tan² x = 0 ⇒ take √ for both sides
∴ tan x = 0
∵ tan 0 = 0 , tan π = 0
∴ x = 0
∴ x = π
<em>OR</em>
∵ tan² x + 2 = 0 ⇒ subtract 2 from both sides
∴ tan² x = -2 ⇒ no square root for negative value
∴ tan² x = -2 is refused
∴ The solutions of the equation are 0 , π
Answer:
yes , an arc can indeed determine the circumference of a circle
Answer:

Step-by-step explanation:
Combine like terms (terms with the same exponent).

"Standard form" means to list terms so the exponents go from high to low (descending order).
Answer:
35 blue shirts
Step-by-step explanation:
7 x 3 = 21
7 x 5 = 35