Help, please! 3x−y=12 x=−6y−15 What is the solution? Show work!

true or false: we want the leading coeffient of a polynomial to be a positive number whenever possible

EastWind [94]

That is false... coefficients in polynomials can lead in either positive or negative

4 0

3 years ago

Solve the oblique triangle where side a has length 10 cm, side c has length 12 cm, and angle beta has measure thirty degrees. Ro

Ugo [173]

Answer:

$Side\ B = 6.0$

$\alpha = 56.3$

$\theta = 93.7$

Step-by-step explanation:

Given

Let the three sides be represented with A, B, C

Let the angles be represented with $\alpha, \beta, \theta$

[See Attachment for Triangle]

$A = 10cm$

$C = 12cm$

$\beta = 30$

What the question is to calculate the third length (Side B) and the other 2 angles ( $\alpha\ and\ \theta$ )

Solving for Side B;

When two angles of a triangle are known, the third side is calculated as thus;

$B^2 = A^2 + C^2 - 2ABCos\beta$

Substitute: $A = 10$ , $C =12$ ; $\beta = 30$

$B^2 = 10^2 + 12^2 - 2 * 10 * 12 *Cos30$

$B^2 = 100 + 144 - 240*0.86602540378$

$B^2 = 100 + 144 - 207.846096907$

$B^2 = 36.153903093$

Take Square root of both sides

$\sqrt{B^2} = \sqrt{36.153903093}$

$B = \sqrt{36.153903093}$

$B = 6.0128115797$

$B = 6.0$ (Approximated)

Calculating Angle $\alpha$

$A^2 = B^2 + C^2 - 2BCCos\alpha$

Substitute: $A = 10$ , $C =12$ ; $B = 6$

$10^2 = 6^2 + 12^2 - 2 * 6 * 12 *Cos\alpha$

$100 = 36 + 144 - 144 *Cos\alpha$

$100 = 180 - 144 *Cos\alpha$

Subtract 180 from both sides

$100 - 180 = 180 - 180 - 144 *Cos\alpha$

$-80 = - 144 *Cos\alpha$

Divide both sides by -144

$\frac{-80}{-144} = \frac{- 144 *Cos\alpha}{-144}$

$\frac{-80}{-144} = Cos\alpha$

$0.5555556 = Cos\alpha$

Take arccos of both sides

$Cos^{-1}(0.5555556) = Cos^{-1}(Cos\alpha)$

$Cos^{-1}(0.5555556) = \alpha$

$56.25098078 = \alpha$

$\alpha = 56.3$ (Approximated)

Calculating $\theta$

Sum of angles in a triangle = 180

Hence;

$\alpha + \beta + \theta = 180$

$30 + 56.3 + \theta = 180$

$86.3 + \theta = 180$

Make $\theta$ the subject of formula

$\theta = 180 - 86.3$

$\theta = 93.7$

5 0

3 years ago

Determine algebraically whether the given function is even, odd, or neither.

uranmaximum [27]

To check whether a function is odd or even, we simply substitute the argument by its negative version, namely "x" by "-x".

if the expression simplifies to resemble the original expression, that simply means the expression is even. If it resembles the original negative expression, is odd.

$\bf g(x)=-2x^3-9\\\\
-------------------------------\\\\
\stackrel{x=-x}{g(-x)}=-2(-x)^3-9\implies g(-x)=-2(-x)(-x)(-x)-9
\\\\\\
g(-x)=+2(x)(x)(x)-9\implies g(-x)=2x^3-9$

well, that doesn't look like the original - 2x³ - 9, so is not even.

and -f(x) would be 2x³ + 9, and that doesn't look like either, so is not odd.

thus is neither.

7 0

3 years ago

PLEASE HELP!!!! WILL GIVE BRAINLIEST!!!In two or more complete sentences explain how you would set up and solve the following eq

olchik [2.2K]

Peter's account is 910-40x, and Marla's account is 470-2x. This is a system, so you must find the number that makes both equations end up with the same number. Basically trial and error. Here is what I did:

Let's try the number 10. 910-400=510 and 470-20=450. I need a higher number.

Let's try 13 next. 910-520=390 and 470-26=444. Now the number has to be lower.

Let's try 12. 910-480=430 and 470-24=446. Close, and a little lower.

11.5 is too low, and 11.7 is too high. 11.6 has Equation 1 at 446 and Equation 2 at 446.8. Very close!

It is somewhere around 11.6. I hope that this can give you a start in figuring it out, because I don't believe in giving the complete answer, because then you do not learn anything from it.

4 0

3 years ago

Read 2 more answers

Please help ASAP and help me find what the value of x is

elixir [45]

Answer:

x=44

Step-by-step explanation:

33+103+x=180

136+x=180

x=44

6 0