Answer:
the question is missing the numbers, so I looked for a similar one and found that screens back in 2017 had a 16:9 ratio and since then it changed to 18.5:9 ratio
the area of the screen is b x a x 0.5
we can form triangles:
old aspect ratio (16:9):
a = 1.778b
h = √(a² + b²)
5.8 = √[(1.778b)² + b²]
5.8 = √(3.16b² + b²)
5.8² = 4.16b²
33.64 = 4.16b²
b² = 33.64 / 4.16 = 8.0865
b = √8.0865 = 2.8437
a = 2.8437 x 1.778 = 5.056
area = 2.8437 x 5.056 x 0.5 = 7.19 in²
new aspect ratio (18.5:9):
a = 2.0556b
h = √(a² + b²)
5.8 = √[(2.0556b)² + b²]
5.8 = √(4.2253b² + b²)
5.8² = 5.2253b²
33.64 = 5.2253b²
b² = 33.64 / 5.2253 = 6.4379
b = √6.4379 = 2.5373
a = 2.5373 x 2.0556 = 5.2157
area = 2.5373 x 5.2157 x 0.5 = 6.62 in²
the actual screen area decreased by 0.57 in² or 7.93%
