Respuesta :

Answer:

-21

Step-by-step explanation:

the formula for the perimeter of a rectangle is 2l+2w. which means twice the length and twice the width added to together.

if you mean this:

x=21+2x

minus x on both sides

0=21-x

add 21 on both sides

21=-x

x=-21

than you subsitute

2×-21=-42

-42+21= -21

The perimeter is than -21

Answer:

-21

Step-by-step explanation:

the formula for the perimeter of a rectangle is 2l+2w. which means twice the length and twice the width added to together.

if you mean this:

x=21+2x

minus x on both sides

0=21-x

add 21 on both sides

21=-x

x=-21

than you subsitute

2×-21=-42

-42+21= -21

The perimeter is than -21