How do you solve #7? the answer is d1=8 and d2=14; but how do you solve it?

8 ft and 14 ft

Step-by-step explanation:

Let one diagonal be x then the other diagonal is 2x - 2

The area (A) of the rhombus is calculated using

A = product of the diagonals, that is

A = x(2x - 2) = 56

Multiply both sides by 2

x(2x - 2) = 112 ← distribute left side

2x² - 2x = 112 ( subtract 112 from both sides )

2x² - 2x - 112 = 0 ← in standard form ( divide through by 2 )

x² - x - 56 = 0

To factor the quadratic

Consider the factors of the constant term (- 56) which sum to give the coefficient of the x- term (- 1)

The factors are - 8 and + 7, since

- 8 × 7 = - 56 and - 8 + 7 = - 1, thus

(x - 8)(x + 7) = 0

Equate each factor to zero and solve for x

x - 8 = 0 ⇒ x = 8

x + 7 = 0 ⇒ x = - 7

However, x > 0 ⇒ x = 8

One diagonal = 8 ft and the other = 2x - 2 = (2 × 8) - 2 = 16 - 2 = 14 ft

d 600 because 15*10*2=300

300+300=600

step-by-step explanation: