What numbers must be added to complete the perfect square?

256

Step-by-step explanation:

Let the number be k

Thus, the equation can be written as:

x² – 32x + k

From the above,

a = 1

b = –32

c = k

The value of k can be obtained as follow:

b² = 4ac

(–32)² = 4 × 1 × k

1024 = 4k

Divide both side by 4

k = 1024 / 4

k = 256

Thus, 256 should be added to x² – 32x to make it a perfect square i.e

x² – 32x + 256

Check

x² – 32x + k

k = 256

x² – 32x + 256

x² – 16x – 16x + 256

x(x – 16) – 16(x – 16)

(x – 16)(x – 16)

(x – 16)² QED

14 ft 7 inches

step-by-step explanation:

since each model inch corresponds to 25 real inches, 7 model inches will correspond to

7×25" = 175"

at 12" per foot, that is 14 feet, 7 inches.