Answer:
The width of the frame is 2 inches
Step-by-step explanation:
The given dimensions of the picture = 7 inches by 7 inches
The area of the picture, A₁ = 7 in. × 7 in. = 49 in.²
The area of the given picture and the frame, A₂ = 81 square inches
Let 'w' represent the width of the frame and whereby the picture is a square, we have;
The area of the picture with the frame, A₂ = 81 in.² = (7 + w) × (7 + w)
A₂ = 81 = (7 + w) × (7 + w) = 49 + 14·w + w²
49 + 14·w + w² - 81 = 0
w² + 14·w - 32 = 0
(x + 16)·(x - 2) = 0
∴ x = -16 or x = 2
Given that 'x' is a natural number, we have;
The width of the frame, x = 2 inches.
