The law of cosines :
A^2 = B^2 + C^2 - 2BC cos A
2^2 = 3^2 + 4^2 - 2 . 3. 4 cos theta
= 21
hope this helps
Answer:
3. 294 m²
4. 185,856 mm²
Step-by-step explanation:
To find the surface area of any figure, you can simply find the sum of the areas of all the sides. In question 3, the figure is a triangular prism that has two triangular bases and three rectangular sides. The measurements for the triangles are b = 9m and h = 6m. The formula for the area of a triangle is base times height divided by 2, or 9 x 6 = 54/2 = 27 m². However, since there are two triangular bases, the area for both is 54 m². The measurements for the other three rectangles are given:
7(10) + 8(10) + 9(10) = 240 m² + 54 m² = 294 m²
The surface area of a cube is much easier since all sides are equal and can be found using the formula:
SA = 6s², where 's' represents the measure of a side.
SA = 6(176)² = 185,856 mm²
Answer:
14
Step-by-step explanation:
