Correct answer: the first choice !
Easy peasy
slope=(change in rise)/(change in run)
aka
slope between points (x1,y1) and (x2,y2) is
slope=(y2-y1)/(x2-x1) since y is rise/up and x is run/leftright
points
(-7,-9) and (-5,-8)
x1=-7
y1=-9
x2=-5
y2=-8
remember minusing a negative means addin a positive
slope=(-8-(-9))/(-5-(-7))=
(-8+9)/(-5+7)=1/2
slope=1/2
positive slopes go from bottom left to top right
since it is less than 1
it is more horizonal than vertical
The top row of matrix A (1, 2, 1) is multiplied with the first column of matrix B (1,0,-1) and the result is 1x1 + 2x0 + 1x -1 = 0 this is row 1 column 1 of the resultant matrix
The top row of matrix A (1,2,1) is multiplied with the second column of matrix B (-1, -1, 1) and the result is 1 x-1 + 2 x -1 + 1 x 1 = -2 , this is row 1 column 2 of the resultant matrix
Repeat with the second row of matrix A (-1,-1.-2) x (1,0,-1) = 1 this is row 2 column 1 of the resultant matrix, multiply the second row of A (-1,-1,-2) x (-1,-1,1) = 0, this is row 2 column 2 of the resultant
Repeat with the third row of matrix A( -1,1,-2) x (1,0, -1) = 1, this is row 3 column 1 of the resultant
the third row of A (-1,1,-2) x( -1,-1,1) = -2, this is row 3 column 2 of the resultant matrix
Matrix AB ( 0,-2/1,0/1,-2)