Answer: 51.75$
Step-by-step explanation: First, turn 15% into the decimal 0.15, then multiply by 45, which equals 6.75. Now add 6.75, which is the amount the waitress got tipped to 45, which equals 51.75$ total.
So lets get to the problem
<span>165°= 135° +30° </span>
<span>To make it easier I'm going to write the same thing like this </span>
<span>165°= 90° + 45°+30° </span>
<span>Sin165° </span>
<span>= Sin ( 90° + 45°+30° ) </span>
<span>= Cos( 45°+30° )..... (∵ Sin(90 + θ)=cosθ </span>
<span>= Cos45°Cos30° - Sin45°Sin30° </span>
<span>Cos165° </span>
<span>= Cos ( 90° + 45°+30° ) </span>
<span>= -Sin( 45°+30° )..... (∵Cos(90 + θ)=-Sinθ </span>
<span>= Sin45°Cos30° + Cos45°Sin30° </span>
<span>Tan165° </span>
<span>= Tan ( 90° + 45°+30° ) </span>
<span>= -Cot( 45°+30° )..... (∵Cot(90 + θ)=-Tanθ </span>
<span>= -1/tan(45°+30°) </span>
<span>= -[1-tan45°.Tan30°]/[tan45°+Tan30°] </span>
<span>Substitute the above values with the following... These should be memorized </span>
<span>Sin 30° = 1/2 </span>
<span>Cos 30° =[Sqrt(3)]/2 </span>
<span>Tan 30° = 1/[Sqrt(3)] </span>
<span>Sin45°=Cos45°=1/[Sqrt(2)] </span>
<span>Tan 45° = 1</span>
Step-by-step explanation:
So you should use headphones while doing writing work and if digital work then take very short brakes during study and concentrate fully.
Answer:
(2, -7)
x = 2
y = -7
Step-by-step explanation:
Let's solve this system of equations by elimination.
Start by multiplying the first equation by 2:

Next, multiply the second equation by 3:

Notice that both equations now have a "6y", meaning we can subtract both equations and thereby eliminating the variable "y" from the equation:

Divide both sides by 23

Substitute 2 for "x" to solve for "y".

Subtract 8 from both sides:

Divide both sides by 3:

Therefore the answer is:

Additional Comments:
Note that we can only divide, subtract, multiply, or add both sides of the equation by the same quantity due to the Division, Subtraction, Multiplication, or Addition Property of Equality. These properties state that if you divide/subtract/multiply/add one side of the equation by one quantity, you must do the same to the other side of the equation so that it remains an equation.
Answer:
Check whether the first and last terms of the trinomial are perfect squares.
Multiply the roots of the first and third terms together.
Compare to the middle terms with the result in step two
If the first and last terms are perfect squares, and the middle term’s coefficient is twice the product of the square roots of the first and last terms
Step-by-step explanation: