Question

A tablet has a 7-in. diagonal screen. The length of the tablet screen is 2.7 in. more than the width of the tablet screen. Find the length and width of the screen. Round to 1 decimal place. Show all work.

Answer 1

Length = 6.1 inches and Width = 3.4 inches

Explanation:

We are told that the diagonal measures 7 inches.

We are also told that the length of the screen is 2.7 inches more than the width.

Let the length be L and width be W.

Thus, L = W + 2.7

Now, since length = W + 2.7 and width = W and diagonal = 7 inches, we can use pythagoras theorem to solve.

Thus;

W² + (W + 2.7)² = 7²

W² + W² + 5.4W + 7.29 = 49

2W² + 5.4W - 41.71 = 0

Using quadratic formula, we have;

W = [-5.4 ± √(5.4² - 4(2 × -41.71))]/(2 × 2)

W = [-5.4 ± √(362.84)]/4

W = -5.4/4 ± 19.05/4

W = (-1.35 + 4.7625) or (-1.35 - 4.7625)

W ≈ 3.4 inches or -6.1

W cannot be negative, thus, W = 3.4 inches

From earlier, we saw that L = W + 2.7

Thus,L = 3.4 + 2.7 = 6.1 inches

So, Length = 6.1 inches and Width = 3.4 inches