What is the solution of the system of equations?

y = –3x + 7
y = 2x – 8

(3,-2)

Step-by-step explanation:

-3x + 7 = 2x - 8

-3x - 2x = -8 - 7

-5x = -15

x = -15/-5

x = 3  

y = 2x - 8

y = 2(3) - 8

y = 6 - 8

y = -2  

solution is (3,-2)

(3,-2)

Step-by-step explanation:

The easiest way to solve this is to realize that in both equations, the ys must have the same value. So the right side of each equation can be equal.

-3x + 7 = 2x - 8            Add 8 to both sides

-3x + 7 + 8 = 2x           Combine

-3x + 15 = 2x                Add 3x to both sides

15 = 2x + 3x                 Combine and exchange sides

5x = 15                         Divide by 5

x = 15/5          

x = 3

Use y = 2x - 8 to solve for y

y = 2(3)  = 8

y = 6 - 8

y = - 2

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

heyyy

step-by-step explanation: