868 is about 870, and 28 is about 30, so your expression would be 870 divided by 30 which would be 29 and the actual answer is 31, so your estimate would be close to your actual answer.
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
What question is that from? I'm talking about ur grade