Answer:
A. 5 < AC < 10
Step-by-step explanation:
If ∆ABC is a right angled triangle, we use the Pythagoras formula:
c² = a² + b²
Where c = longest side
When given sides AB, AC and BC, the formula becomes:
AB² = AC² + BC²
Where AB = Longest side
In the question,
AB = 10 and BC = 5.
10² = AC² + 5²
AC² = 10² - 5²
AC² = 100 - 25
AC² = 75
AC = √75
AC = 8.6602540378
Therefore, the expression that is always true = A. 5 < AC < 10
Reorder the terms: 2n + -5(5 + n) = 8n + 3(1 + -5n) 2n + (5 * -5 + n * -5) = 8n + 3(1 + -5n) 2n + (-25 + -5n) = 8n + 3(1 + -5n) Reorder the terms: -25 + 2n + -5n = 8n + 3(1 + -5n) Combine like terms: 2n + -5n = -3n -25 + -3n = 8n + 3(1 + -5n) -25 + -3n = 8n + (1 * 3 + -5n * 3) -25 + -3n = 8n + (3 + -15n) Reorder the terms: -25 + -3n = 3 + 8n + -15n Combine like terms: 8n + -15n = -7n -25 + -3n = 3 + -7n Solving -25 + -3n = 3 + -7n Solving for variable 'n'. Move all terms containing n to the left, all other terms to the right. Add '7n' to each side of the equation. -25 + -3n + 7n = 3 + -7n + 7n Combine like terms: -3n + 7n = 4n -25 + 4n = 3 + -7n + 7n Combine like terms: -7n + 7n = 0 -25 + 4n = 3 + 0 -25 + 4n = 3 Add '25' to each side of the equation. -25 + 25 + 4n = 3 + 25 Combine like terms: -25 + 25 = 0 0 + 4n = 3 + 25 4n = 3 + 25 Combine like terms: 3 + 25 = 28 4n = 28 Divide each side by '4'. n = 7 Simplifying n = 7
Answer:
11
Step-by-step explanation:
Answer:
surface area is 39
Step-by-step explanation:
add the areas of each geometric figure making up the composite 3D figure.
first 3D figure
2+2+6+6
=16---eq 1
from third 3D figure
4+4+10+5
= 23
from 1 and 2
16+23
= 39
may be!! I'm not sure bout this answer
Answer:
Step-by-step explanation:
21
