Hey, I need help badly!

Question

dumbsearch2 · Answer

attachment

lyrae · Answer

I which point does the curve and the line intersect?

dumbsearch2 · Answer

1, 1?

lyrae · Answer

Yep, and that's your answer. When sloving graphically the solution to any system of  equations (linear or nonlinear) are points where the function curves, lines etc. intersect.

lyrae · Answer

are all the points*

Nonlinear systems usually have several solutions.

dumbsearch2 · Answer

Thank you! :)

And this?

lyrae · Answer

Np :)

All points in the green shaded area, so you'll have to check if the the points given in the answers options are in that area or not.

lyrae · Answer

And it looks like (1,1) is the only one present there.

dumbsearch2 · Answer

So I'm correct! Yupppeee :-)

dumbsearch2 · Answer

It's D here, right? @Lyrae

lyrae · Answer

Yup :)

dumbsearch2 · Answer

@Lyrae 

For this I graph each one, rite?

lyrae · Answer

Yes that's one way to do it.

dumbsearch2 · Answer

I tried, but too many match.

lyrae · Answer

You can also insert the x and y-values of each point into inequalities and see one of them one (or several) of them are violated.

dumbsearch2 · Answer

Ahh! Will do. Plug in, eh?

dumbsearch2 · Answer

@Lyrae Aye, you're awesome. What's your name?

lyrae · Answer

Carl

lyrae · Answer

And thx :)

dumbsearch2 · Answer

So the answer is B?

dumbsearch2 · Answer

It was True for each of the equations when I plugged in for B. (-4, -15)

dumbsearch2 · Answer

Thanks again, Carl.

lyrae · Answer

Yup, that's what i got too. 

Anytime :)

dumbsearch2 · Answer

I don't know what to do for this problem @Lyrae

lyrae · Answer

It's a point outside the shaded area, and not any of the red lines.

lyrae · Answer

For the previous one i noticed there are actually another point witch satisfies all the inequalities (-4,-4).

dumbsearch2 · Answer

So was it B.	(-4, -15)

for that one or

	C.	(-4, -4)

lyrae · Answer

The assignment also mentions that you have to select a point on a vertice.

dumbsearch2 · Answer

So?

lyrae · Answer

This means that you have to check where a bunch of lines intersect.

lyrae · Answer

y = 3x-5                   
y = -1/2*x + 2      =>  x = 2, y = 1

y = -4
y = 3x-5                => x = 1/3, y = -4

y = -4
y = -1/2*x + 2      => x = 12, y = -4

None of the x, y pairs maches a point in the answers.

|dw:1418939854308:dw|

Not any of the point are one the lines either.

lyrae · Answer

Therefore it can't be any of those two points (B or C). And when looking again you see that (-4, 4) also is a valid point, and it's on the the line (boundary) of the second inequality.

x= -4
y = -1/2 x + 2 = -1/2 * -4 + 2 = 4      => x = -4, y = 4