Answer:
1.4in
Step-by-step explanation:
Length of Photo = 4in
Width of Photo = 3in
Unknown:
Value of X = ?
Solution:
Follow these steps:
Area of a rectangle = l x w
Since the photo is a rectangle; area of photo:
Area of photo = 4in x 3in = 12in²
For the area of the ad;
Length of ad = 4 + x
Width of ad = 3 + x
Given that,
the area of the photo = area of ad
12in² = area of ad
Area of ad = 24in²
Area of the ad;
(4 + x) (3 + x) = 24
12 + 4x + 3x + x² = 24
12 + 7x + x² = 24
x² + 7x = 24 - 12
x² + 7x = 12
x² + 7x - 12 = 0
Using the almighty formula where
a = 1, b = 7 and c = -12
x =
x = or
x = 1.4 or -8.4
therefore the answer is 1.4in
x is 1.4in