Jasmira has a new corner shelving unit that is triangular. The unit has three identical oblique triangle shelves. Jasmira wants to put some shelving paper down but isn’t sure how much to buy. If one side of each triangle is 22 inches, an adjoining side is 35 inches, and the angle formed between them is 87 degrees, then how much paper (to the nearest square inch) does she need to cover all 3 shelves?(1 point) Responses 660 inches2 660 inches squared 1,153 inches2 1,153 inches squared 2,038 inches2 2,038 inches squared 1,647 inches2

1 answer

To find the area of one triangular shelf, we can use the formula for the area of a triangle given two sides and the included angle:

\[ \text{Area} = \frac{1}{2} \times a \times b \times \sin(C) \]

where:

  • \( a \) and \( b \) are the lengths of the two sides,
  • \( C \) is the angle between those sides.

Given:

  • \( a = 22 \) inches
  • \( b = 35 \) inches
  • Angle \( C = 87^\circ \)

Let's calculate the area of one shelf:

  1. Calculate \(\sin(87^\circ)\): \[ \sin(87^\circ) \approx 0.998 \]

  2. Plug the values into the area formula: \[ \text{Area} = \frac{1}{2} \times 22 \times 35 \times 0.998 \]

  3. Calculate: \[ \text{Area} = \frac{1}{2} \times 770 \times 0.998 \] \[ \text{Area} \approx \frac{770 \times 0.998}{2} \approx \frac{767.46}{2} \approx 383.73 \text{ square inches} \]

  4. Round to the nearest square inch: \[ \text{Area} \approx 384 \text{ square inches} \]

Since Jasmira has three identical shelves, the total area covered by the shelving paper will be:

\[ \text{Total Area} = 3 \times 384 \approx 1152 \text{ square inches} \]

Thus, rounding to the nearest square inch, the total area is:

\[ \text{Total Area} \approx 1152 \text{ square inches} \]

However, we should check the options given closely. The nearest square inch calculated is closest to 1,153 inches².

Therefore, the answer is:

1,153 inches squared.