Margot is sewing a ribbon on a seam along the perimeter of a square pillow. The side length of the pillow is 23-1 inches. She plans to make a similar pillow, including the ribbon, whose side length is 4x-7 inches. What expression can be used for the length of ribbon that she needs for both pillows, and what is the length if x = 3.5? 2x14x-6: 22.0 inches

2x14x-6; 32.5 inches

4(2x+4x-6) 88.0 inches

4(2x +48-6:) 130.0 inches

D. 4(2x² + 4x - 6); 130.0 inches

Step-by-step explanation:

Margot is sewing a ribbon on a seam along the perimeter of a square pillow. The side length of the pillow is 2x²+1 inches. She plans to make a similar pillow, including the ribbon, whose side length is 4x−7 inches. What expression can be used for the length of ribbon that she needs for both pillows, and what is the length if x = 3.5?

2x2+4x−6; 22.0 inches

2x2+4x−6; 32.5 inches

4(2x2+4x−6;) 88.0 inches

4(2x2+4x−6;) 130.0 inches

Perimeter of a square = 4 * side length

1- First square pillow

length = 2x²+1 in

Perimeter of first pillow = 4 * (2x²+1) in

Second square pillow

length = 4x-7 in

Perimeter of second pillow = 4(4x-7) in

Total ribbon length required = perimeter of first square pillow + perimeter of second square pillow

Total ribbon length required = 4(2x²+1) + 4(4x-7)

Factorise

4 is the common factor

=4(2x²+1)+(4x-7)

=4(2x²+1+4x-7)

=4(2x²+4x-6)

Total ribbon length required=4(2x²+4x-6)

If x=3.5

Total ribbon length required=4(2x²+4x-6)

=4{2(3.5)²+4(3.5)-6}

=4{2(12.25)+14-6)

=4(24.5+14-6)

=4(32.5)

=130.0 inches

1.4

2.3

step-by-step explanation:

the formula for the constant of variation is

y= kx

divide each side by x

y/x =kx/x

y/x =k

we know a and y

1.   y/x = k

4/1 =4

check the other values to make sure they are the same

8/2 = 4   12/3 =4   and 16/4 =4  

the constant of variation is 4

2.   y/x = k

3/1 =3

check the other values to make sure they are the same

6/2 = 3   9/3 =3   and 12/4 =3  

the constant of variation is 3

it is x=-4

step-by-step explanation: