Question

@jim_thompson5910 What Is the equation of a line (in standard form) that passes through (-3,0) and (-1,-4)

I got 2x + y = 6

correct ?

Answer 1

incorrect

2x + y = 6

2(-3) + 0 = 6 ... replace (x,y) with (-3,0)

-6 + 0 =6

-6 = 6 ... this is false, so (-3,0) is NOT on the line 2x+y = 6

Answer 2

ok idk where i went wrong..

first is slope which i got -2 correct ?

Answer 3

then, point-slope form and i got y - 0 = -2(x - -3)

Answer 4

then slope intercept form and i got y = -2x + 6

Answer 5

well y - 0 = -2(x - (-3)) turns into y = -2(x + 3) and that turns into y = -2x - 6

Answer 6

wait why does it turn into that

Answer 7

because the two negatives make a positive

Answer 8

which is why y - 0 = -2(x - (-3)) turns into y = -2(x + 3)

Answer 9

then you distribute it to y = -2x - 6

Answer 10

ok so then...

what do i do ?

Answer 11

you add 2x to both sides

y = -2x - 6

y+2x = -2x - 6+2x

2x+y = -6

Answer 12

I recommend you check both points in 2x+y = -6

Answer 13

and thats the standard form ?

Answer 14

yes it's in Ax + By = C form

Answer 15

Thank you

Answer 16

np