X 1) a) Placer trois points A, B et c non
lignés.
» Construire la droite (d) parallèle à la droite
AB) et passant par le point C.
:) Construire la perpendiculaire (4) à la droite
AB) et passant par le point A.
?) Justifier que les droites (d) et (4) sont
perpendiculaires.

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.