Question

Help with these:/ I don't understand

Answer 1

can you find slope of any given line ?

Answer 2

like say , x-5y = -10 is a line.
can you find slope of this line first ?

Answer 3

Uh no not really... with a quick review I probably can

Answer 4

good,
so i have x-5y =-10
i will try to isolate y and bring it in the form y=mx+c where m=slope

so,
x=5y-10
5y = x+10
y= (1/5)x +2

got this ?

Answer 5

Yeah I got it

Answer 6

cool, so can you find the slope of x -3y=9 line ? in same way

Answer 7

oh and i forgot to mention,
y= (1/5)x +2

comparing with y=mx+c
gives, m=slope = 1/5

Answer 8

x-37=9
-3y=x+9
Y=(1/3)x+3

Answer 9

So slope would be 1/3 I assume?

Answer 10

correct! :)
now try to find slopes of other 3 lines also!
and tell me, so that i will verify :)

Answer 11

4x+2y=5
2y=-4x+5
Y-(-1/2)x+2.5 ?

Answer 12

2y=-4x+5 is correct, but then divide both sides by 2
what u get ?

Answer 13

10x-5y=8
-5y=10x+8
Y=-2x+1.6?

Answer 14

10x-5y=8
-5y=10x+8 <<<<<<NO!

-5y = -10x +8

Answer 15

and you would get y=-2+2.5

Answer 16

Ahh okay -10 so the problem would come out with a positive 2x

Answer 17

yes, so the slope will be m= 2 , right ?

Answer 18

Yes

Answer 19

4x+2y=5 slope = -2
make a note of all slopes, we'll need them

Answer 20

and what about last line ?

Answer 21

4x+y=-1
Y=-4x-1

Answer 22

so, slope =?

Answer 23

-4

Answer 24

Good!
now here's the rule :
slope of parallel lines are equal!
so, for the last one, slope of line parallel to 4x+y=-1 will also be m=-4 :)
so, for last, the correct option will be `C) m=-4`
got this ?

in same way, can you match the 2nd last and 3rd last ?

Answer 25

Yeah I got it, Thanks a ton man. You need to be my teacher xD

Answer 26

haha, :)
but we still require to do the 1st 2 !

Answer 27

another rule,
`product of slopes of perpendicular lines = -1 `

so, for 1st one we had slope = 1/5
let slope of perpendicular line be m.
so,
\(\Large m\times (1/5)=-1\)
find m from here :)

Answer 28

1st one is m=1/5?
2cnd one is m=1/3?

It seems like these would be the answers but they are not possible to be selected.

Answer 29

Ahhhh okay

Answer 30

because perpendicular lines follow different rule :)

Answer 31

Well I still don't exactly get how it goes from (1/5) to -1...

Answer 32

product of slopes = -1 is the rule
so, m (1/5) =-1
multiplying by 5,
m = -5

got this ?

Answer 33

multiplying by 5 on both sides.

Answer 34

I'm confused on the product of slopes part, I get the multiplying on both sides. So like can you explain the product of slopes rule.. I tried looking it up on google but nothing I can comprehend really comes up.

Answer 35

if say line 1 has slope M1
and line 2 has slope M2
now if these 2 lines are perpendicular to each other, then M1*M2 =-1

Answer 36

another way to remember the same thing is, the slope of line is negative reciprocal of the perpendicular line,
so, slope of line perpendicular to line with slope 1/5 will be - (1/(1/5)) = -5

Answer 37

so, thats your 1st one, m =-5

for 2nd one, we had slope = 1/3, so
m *(1/3) = -1
so, m=-3 is the answer to 2nd one :)

Answer 38

Okay, so basically whenever there is a fraction just take (1/_) blank space number lol

Answer 39

you forgot the negative :P
-1/ stuff

Answer 40

but this only applies to perpendicular lines

Answer 41

for parallel lines, slope are equal

Answer 42

Oh I see says the blind man

Answer 43

what who ?

Answer 44

lol

Answer 45

i hope you got the entire problem clearly ?

Answer 46

ask if any doubts anywhere

Answer 47

Yeah I get it now man thanks a ton

Answer 48

welcome ^_^