Question

Tính:

a)ax+ay+bx+by biết a+b=-3;x+y=13

b)ax-ay+bx-by biết a+b=-7;x-y=-18

 

 

 

 

 

 

 

Answer 1

a)\(ax+ay+bx+by\)

\(=a\left(x+y\right)+b\left(x+y\right)\)

\(=\left(a+b\right)\left(x+y\right)\)

\(=-3\cdot13\)

\(=-39\)

 

b)\(ax-ay+bx-by\)

\(=a\left(x-y\right)+b\left(x-y\right)\)

\(=\left(a+b\right)\left(x-y\right)\)

\(=\left(-7\right)\left(-18\right)\)

\(=126\)

Answer 2

a*(x+y)+b-(x+y)

=(a+b)*(x+y)

=-3*13

=-39

 

Answer 3

câu b

=a*(x-y)+b*(x-y)

=(a+b)*(x-y)

=-7*-18

=-126 tick vs nha