Answer:
Step-by-step explanation:
three days?
Answer:
x = √30 or -√30
Step-by-step explanation:
480 - 16x^2 = 0
divide both sides by 16
30 - x^2 = 0
-x^2 + 30 = 0
-x^2 = -30
X^2 = 30
x = ± √30
x = √30 or -√30
Answer:
x = -5, and y = -6
Step-by-step explanation:
Suppose that we have two equations:
A = B
and
C = D
combining the equations means that we will do:
First we multiply both whole equations by constants:
k*(A = B) ---> k*A = k*B
j*(C = D) ----> j*C = j*D
And then we "add" them:
k*A + j*C = k*B + j*D
Now we have the equations:
-x - y = 11
4*x - 5*y = 10
We want to add them in a given form that one of the variables cancels, so we can solve it for the other variable.
Then we can take the first equation:
-x - y = 11
and multiply both sides by 4.
4*(-x - y = 11)
Then we get:
4*(-x - y) = 4*11
-4*x - 4*y = 44
Now we have the two equations:
-4*x - 4*y = 44
4*x - 5*y = 10
(here we can think that we multiplied the second equation by 1, then we have k = 4, and j = 1)
If we add them, we get:
(-4*x - 4*y) + (4*x - 5*y) = 10 + 44
-4*x - 4*y + 4*x - 5*y = 54
-9*y = 54
So we combined the equations and now ended with an equation that is really easy to solve for y.
y = 54/-9 = -6
Now that we know the value of y, we can simply replace it in one of the two equations to get the value of x.
-x - y = 11
-x - (-6) = 11
-x + 6 = 11
-x = 11 -6 = 5
-x = 5
x = -5
Then:
x = -5, and y = -6
<h3>
Answers:</h3>
- A. T <-> U is a <u>biconditional</u>
- B. (A & B) v (C & D) is a <u>disjunction</u>
- C. R -> ~S is a <u>conditional</u>
- D. P & Q is a <u>conjunction</u>
- E. ~(R v P) is a <u>negation</u>
========================================
Explanations:
- A biconditional is anything in the form A <-> B. This is a compact way of saying (A -> B) & (B -> A). We replace A and B with logical statements.
- Disjunctions are of the basic form A v B. The "v" basically means "or".
- Any conditional is of the form "if... then...". For example, "if it rains, then it gets wet outside" is a conditional. In terms of logic symbols, we write A -> B to mean "if A, then B".
- Conjunctions are whenever we combine two logical statements with an "and" or an ampersand symbol. The basic form is A & B
- Negations are the complete opposite of the original. If the original is P, then the negation is ~P, which is read as "not P".
Answer:
2) 162°, 72°, 108°
3) 144°, 54°, 126°
Step-by-step explanation:
1) Multiply the equation by 2sin(θ) to get an equation that looks like ...
sin(θ) = <some numerical expression>
Use your knowledge of the sines of special angles to find two angles that have this sine value. (The attached table along with the relations discussed below will get you there.)
____
2, 3) You need to review the meaning of "supplement".
It is true that ...
sin(θ) = sin(θ+360°),
but it is also true that ...
sin(θ) = sin(180°-θ) . . . . the supplement of the angle
This latter relation is the one applicable to this question.
__
Similarly, it is true that ...
cos(θ) = -cos(θ+180°),
but it is also true that ...
cos(θ) = -cos(180°-θ) . . . . the supplement of the angle
As above, it is this latter relation that applies to problems 2 and 3.
