Danielle and tracy are building a rectangular sandbox. danielle has two boards that are equal in length, and tracy has two boards that are each 5 feet longer than danielle’s. they use the four boards as the four sides of their sandbox. use the variable x to write an algebraic expression to relate the perimeter of the sandbox to the length of one of danielle’s boards.

Step-by-step explanation:

Let

x -----> the length of Danielle's board in feet

y ----> the length of Tracy's board in feet

we know that

----> equation A

The perimeter of the sandbox is equal to

----> equation B

substitute equation A in equation B

b is the answer that makes most sense

step-by-step explanation:

x = ± 6i

step-by-step explanation:

x^2 = -36

take the square root of each side

sqrt(x^2) = sqrt(-36)

we know sqrt(ab) = sqrt(a) sqrt(b)

x = ±sqrt(36) sqrt(-1)

we know that sqrt (-1) = i

x = ± 6i