Arectangle has a width of 10 centimeters. the rectangle's length is 4 times its width. what is the perimeter of the rectangle?

100 cm.

Step-by-step explanation:

We have been given that a rectangle has a width of 10 centimeters. The rectangle's length is 4 times its width.

The length of rectangle would be .

We know that perimeter of rectangle is 2 times the sum of length and width of rectangle.

Therefore, the perimeter of our given rectangle would be 100 cm.

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

nope.   happens to me as well.

-aparri