Choose the equation below that represents the line that passes through the point (7, -2) and has a slope of -3 A. y - 2 = -3(x + 7)
B. y + 2 = -3(x - 7)
C. y + 7 = -3(x - 2)
D. y - 7 = -3(x + 2)

B

Step-by-step explanation:

The equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

Here m = - 3 and (a, b) = (7, - 2 ), thus

y - (- 2) = - 3(x - 7) , that is

y + 2 = - 3(x - 7) → B

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

you are uyytr tyy

step-by-step explanation: