What is the answer to this question? Please Help.

x = 2, y= 3

Step-by-step explanation:

y = -2x+7

y = 5x-7

Since the equations are both equal to y, set them equal to each other

-2x+7 = 5x-7

Add 2x to each side

-2x+7 +2x= 5x+2x-7

7 = 7x -7

Add 7 to each side

7+7 = 7x

14 = 7x

Divide by 7

14/7 = 7x/7

2 = x

Now find y

y = 5x-7

y = 5*2 -7

y = 10-7

y =3

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

56

step-by-step explanation: