The work that yi did to find the greatest common factor of 42 and 63 is shown below. factors of 42: 1, 2, 3, 6, 7, 14, 21, 42 factors of 63: 1, 7, 9, 63 the greatest common factor is 7. what is yi’s error? yi did not list all the factors of 63. yi listed multiples for each number instead of factors. yi did not list all the factors of 42. yi found the least common multiple.

A. Yi did not list all the factors of 63.

Step-by-step explanation:

We have been given Yi's work to find greatest common factor of 42 and 63 as shown below:

Factors of 42: 1, 2, 3, 6, 7, 14, 21, 42

Factors of 63: 1, 7, 9, 63

Yi found that greatest common factor is 7.

To find Yi's error, let us check our given choices one by one.

A. Yi did not list all the factors of 63.

Let us find factors of 63.

Factors of 63: 1, 3, 7, 9, 21, 63

Upon looking at Yi's factors of 63, we can see that Yi did not list 3 and 21 as factors of 63, therefore, option A is the correct choice.

A. yi did not list all the factors of 63

Step-by-step explanation:

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