Y=9x+3>> is this true, false, or open??

2 answers:

8 0

First you have to know the value of either x or y. If x is 2, and y is 20, it would be false.

But if x is 2 and y is 21, it would be true.

So, the equation is open!

fomenos3 years ago

8 0

This is redundant, it can be rewritten as y=3x+1. to better understand this we can easily graph this line in the form y=mx+b.

You might be interested in

Evaluate Dx / ^ 9-8x - x2^

Solnce55 [7]

It depends on what you mean by the delimiting carats "^"...

Since you use parentheses appropriately in the answer choices, I'm going to go out on a limb here and assume something like "^x^" stands for $\sqrt x$ .

In that case, you want to find the antiderivative,

$\displaystyle\int\frac{\mathrm dx}{\sqrt{9-8x-x^2}}$

Complete the square in the denominator:

$9-8x-x^2=25-(16+8x+x^2)=5^2-(x+4)^2$

Now substitute $x+4=5\sin y$ , so that $\mathrm dx=5\cos y\,\mathrm dy$ . Then

$\displaystyle\int\frac{\mathrm dx}{\sqrt{9-8x-x^2}}=\int\frac{5\cos y}{\sqrt{5^2-(5\sin y)^2}}\,\mathrm dy$

which simplifies to

$\displaystyle\int\frac{5\cos 
y}{5\sqrt{1-\sin^2y}}\,\mathrm dy=\int\frac{\cos y}{\sqrt{\cos^2y}}\,\mathrm dy$

Now, recall that $\sqrt{x^2}=|x|$ . But we want the substitution we made to be reversible, so that

$x+4=5\sin y\iff y=\sin^{-1}\left(\dfrac{x+4}5\right)$

which implies that $-\dfrac\pi2\le y\le\dfrac\pi2$ . (This is the range of the inverse sine function.)

Under these conditions, we have $\cos y\ge0$ , which lets us reduce $\sqrt{\cos^2y}=|\cos y|=\cos y$ . Finally,

$\displaystyle\int\frac{\cos y}{\cos y}\,\mathrm dy=\int\mathrm dy=y+C$

and back-substituting to get this in terms of $x$ yields

$\displaystyle\int\frac{\mathrm dx}{\sqrt{9-8x-x^2}}=\sin^{-1}\left(\frac{x+4}5\right)+C$

4 0

3 years ago

Answer to 24 pls and thanks :D ik its super simple but im not very good at this and i forgot how to do it, and you guys get like

iogann1982 [59]

There is no picture given for us to answer the question!

8 0

4 years ago

Find an equivalent expression to 3(4m-2)-2(m+5)

Anuta_ua [19.1K]

3(4m-2)-2(m+5)

Distribute.

12m-6-2m-10

12m-2m= 10m

-6-10= -16

10m-16

I hope this helps!
~kaikers

3 0

3 years ago