Question

Point slope form help ? GIVING MEDAL!

Answer 1

11. write an equation in point-slope form for the line through the given point with the given slope. (5,2); m =3 (1 point)

Answer 2

point slope form is y - y1 = m(x - x1)
slope(m) = 3
(5,2) x1 = 5 and y1 = 2
now just sub
y - y1 = m(x - x1)
y - 2 = 3(x - 5) ===> point slope form

Answer 3

any questions ?

Answer 4

Yea could you do one more that has a fraction in it?

Answer 5

lets see it

Answer 6

(-4, -2); m = -1/2

Answer 7

y-y1=m(x-x1)

y1= a know y point
x1=a known x point
y1 and x1=ordered pair
m=slope
just substitute the variables for the numbers

Answer 8

y - y1 = m(x - x1)
m = -1/2
(-4,-2) x1 = -4 and y1 = -2
now we sub
y - y1 = m(x - x1)
y - (-2) = -1/2(x - (-4)
y + 2 = -1/2(x + 4) ===> point slope form

Answer 9

you have to be careful with ones that have negative x's and y's, because two negatives multiplied together give you a positive

Answer 10

ill write that down,thanks so much

Answer 11

your welcome :)

Answer 12

what about decimals?

Answer 13

what about them ? Give me an example and I will show you

Answer 14

-
(5,-6); m = -0.38

Answer 15

y - y1 = m(x - x1)
m = -0.38
(5,-6) x1 = 5 and y1 = -6
sub
y - (-6) = -0.38(x - 5)
y + 6 = -0.38(x - 5) ===> point slope form

you do it the same way

Answer 16

understand ?

Answer 17

yea i just wanted to make sure i was doing everything right ,do you know anything about standard form using integers?

Answer 18

I know standard form is Ax + By = C.....and standard form does not allow fractions .

Answer 19

i have two that i dont understand and im suppose to write them in standard form

Answer 20

Y= -2/3x + 7

y= -0.4x + 0.3

Answer 21

y = -2/3x + 7 (we do not want fractions, so multiply the entire equation by the LCD, which is 3.
(3)y = -2/3(3) + 7(3)
3y = -2x + 21 -- add 2x to both sides
2x + 3y = 21 ===> standard form

y = -0.4x + 0.3 (No decimals are allowed in standard form, so we will multiply the entire equation by 10.
(10)y = -0.4x(10) + 0.3(10)
10y = -4x + 3 -- add 4x to both sides
4x + 10y = 3 ===> standard form

Answer 22

any questions ?

Answer 23

i got the exact same answers ! i was a bit confused on formula but i got it ! thanks so much now before you go i have one last question...please tell me you know the whole parallel,perpendicular thing?

Answer 24

I can try...what you got

Answer 25

ok heres the first, are the pair parallel,perpendicular or neither
y= -2x + 4

-5x + 10y = 5

Answer 26

to do this, we need to find the slope of each equation. Parallel lines will have the same slope. Perpendicular lines will have negative reciprocal slopes....all that means is flip the slope and change the sign...for instance -1/2 is perpendicular to 2 (see how I flipped the slope and changed the sign)
ok...now lets do this...
In y = mx + b form, the slope is in the m position. So lets put the equations in y = mx + b form.
y = -2x + 4 -- this is already in y = mx + b form and -2 is in the m position, so -2 is the slope of this equation.
-5x + 10y = 5 -- reduce
-x + 2y = 5 -- add x to both sides
2y = x + 5 -- divide by 2
y = 1/2x + 5/2 --- slope is 1/2

now look at your slopes... -2 and 1/2. These are negative reciprocals of each other, therefore, the equations are perpendicular.

Answer 27

does that help you understand it better ?

Answer 28

ok so what if there were paranthases like this one
y = (-1/5)x + 6
-2x + 10y = 5

Answer 29

you want to find if these are parallel/perpendicular or neither ?

Answer 30

yes

Answer 31

you will need to find the slope by putting them in y = mx + b form.
y = -1/5x + 6 -- already in y = mx + b form and -1/5 is your slope.

-2x + 10y = 5 -- add 2x to both sides
10y = 2x + 5 -- divide by 10
y = 2/10x + 5/10
y = 1/5x + 1/2 -- slope is 1/5

slope are -1/5 and 1/5. They are not the same and they are not negative reciprocals of each other. Therefore, they are neither

Answer 32

ahhh omg thank you so so much!

Answer 33

no problem :)