The length of rectangle is twice its width. the perimeter of the rectangle is 126 feet

length = 42 feet , width = 21 feet .

Step-by-step explanation:

Given  : The length of rectangle is twice its width. The perimeter of the rectangle is 126 feet.

To find : Find the width , length.

Solution : We have given  

Length = 2 * Width .

Perimeter = 126 feet  .

Let length = l

Width = w .

Perimeter = 2 ( length +  width )

Plug the values

126  = 2 ( 2 w + w )

126 = 2 ( 3w).

126 = 6w .

On dividing both sides by the number 6

w = 21 feet .

Width = 21 feet .

Length = 2 * 21= 42 feet .

Therefore, length = 42 feet , width = 21 feet .

b

step-by-step explanation:

given

- 2 (3x + 12y - 5 - 17x - 16y + 4 )

simplify the parenthesis by collecting like terms

= - 2 (- 14x - 4y - 1) ← distribute the parenthesis by - 2

= 28x + 8y + 2 → b

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4