Answer:
8 11/100, 8.11, Hope this helpe :)
Step-by-step explanation:
Answer:
Step-by-step explanation:
Let the sides be a, b and c.
<h3>Given</h3>
The length of one side of a triangle is 2 feet less than three times the length of its second side
The length of the third side is 3/4 of the sum of the lengths of the first two sides:
The perimeter of the triangle is 17.5 feet:
<h3>Solution</h3>
Substitute a with b in the second equation:
- c = (3/4)(3b - 2 + b) = (3/4)(4b - 2) = (3/4)(4b) - (3/4)(2) = 3b - 1.5
Now substitute a and c with b in the third equation and solve for b:
- 3b - 2 + b + 3b - 1.5 = 17.5
- 7b - 3.5 = 17.5
- 7b = 17.5 + 3.5
- 7b = 21
- b = 3
Find the value of a:
- a = 3b - 2 = 3*3 - 2 = 9 - 2 = 7
Find the value of c:
- c = 3b - 1.5 = 3*3 - 1.5 = 9 - 1.5 = 7.5
The sides of the triangle are:
- a = 7 feet, b = 3 feet, c = 7.5 feet
Answer:
SA = 1,176 ft².
Step-by-step explanation:
To find the surface area of the triangular prism, we can solve for the rectangular base, both triangular faces, and lateral sides separately.
For the rectangular base: (Use formula l×w)
20 × 18 = 360 ft²
For the triangular faces: (Use formula 1/2(b·h)
1/2(18 × 12) = 108 ft²
Since there are two faces, we need to double the amount.
108 × 2 = 216 ft².
Finally, solve for the lateral sides:
20 × 15 = 300 ft².
There are two sides, so:
300 × 2 = 600 ft².
Add up all of these areas:
600 + 216 + 360 = 1,176 ft²
Work backwards with pythagoras' theorem:
c^2=a^2+b^2
Here, a and b both equal to x. Therefore, you can write this as 8^2=2x^2. So 64=2x^2. Sqrt on both sides to give you 8=2x, hence x=4. However I must warn you that this working out may have a flaw, as I found that x actually equals to 5.66
