David has a rectangle and a right triangle. -The length of the rectangle is 5 more than its width, w.
-The length of the shorter leg of the triangle is equal to the rectangle's width.
-The length of the longer leg of the triangle is twice the length of the rectangle.

Which function f(w), represents the combined area of the rectangle and the triangle?
A) f(w)=2w^2+10w
B) f(w)=3w^2+15w
C) f(w)= w^2+10w+25
D) f(w)= w^2+15w+50

2

step-by-step explanation:

vvvvv

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

i dony know

step-by-step explanation: