now, bear in mind that all these ones are lines, and to graph a line all you need is two points, so let's pick a couple of random values for say "x" and let's see what we get for "y" and that's our x,y point.
3)
![9x+4y=-16\implies \stackrel{\textit{using x = 0}~\hfill }{9(0)+4y=-16}\implies 4y=-16 \\\\\\ y=\cfrac{-16}{4}\implies y=-4~\hspace{10em}(0~~,~~-4) \\\\[-0.35em] ~\dotfill\\\\ 9x+4y=-16\implies \stackrel{\textit{using x = -4}~\hfill }{9(-4)+4y=-16}\implies -36+4y=-16 \\\\\\ 4y=20\implies y = \cfrac{20}{4}\implies y = 5~\hspace{10em}(-4~~,~~5)](https://tex.z-dn.net/?f=9x%2B4y%3D-16%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Busing%20x%20%3D%200%7D~%5Chfill%20%7D%7B9%280%29%2B4y%3D-16%7D%5Cimplies%204y%3D-16%20%5C%5C%5C%5C%5C%5C%20y%3D%5Ccfrac%7B-16%7D%7B4%7D%5Cimplies%20y%3D-4~%5Chspace%7B10em%7D%280~~%2C~~-4%29%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%209x%2B4y%3D-16%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Busing%20x%20%3D%20-4%7D~%5Chfill%20%7D%7B9%28-4%29%2B4y%3D-16%7D%5Cimplies%20-36%2B4y%3D-16%20%5C%5C%5C%5C%5C%5C%204y%3D20%5Cimplies%20y%20%3D%20%5Ccfrac%7B20%7D%7B4%7D%5Cimplies%20y%20%3D%205~%5Chspace%7B10em%7D%28-4~~%2C~~5%29)
check the red line in the picture below.
4)

check the blue line in the picture below.
Answer:
$33.60
Step-by-step explanation:
Since 20 percent is off, you only need to pay for 80% of the jeans. Therefore, you do 8/10 x 42 = 33.6
Answer:
3F
Step-by-step explanation:
Force = k * x
so k = force/distance = F/2
if you were to duplicate the distance 2 times more, the F must also do so so that it's proportional
so F*2 = 2F but since it says additional 4cm, you will need to add the initial one and this one so that it's 6cm in total.
2F + F = 3F
Answer:
0.027,
, 23%, 0.29, 
Step-by-step explanation:
Here we have to convert the fractions and percents to decimal form, then we have to arrange them from smallest to largest.

23% = 

0.29
0.027
Now we have to arrange from smallest to largest.
0.027 < 0.167 < 0.23 < 0.29<0.6
From smallest to largest
0.027,
, 23%, 0.29,
7pm the next day because 23 hours past 8:00pm would just drop one hour