Answer: The angle of elevation would be 36.87 degrees (approximately)
Step-by-step explanation: Please refer to the attached diagram for details
The 30-foot ladder reaches a point in the building which is point A. The height at which the ladder touches the building is 18 feet (that is, the height of the building, line AC. The angle of elevation from the ground is at angle B, the angle which the ladder forms with the ground.
So we have a right angled triangle ABC, with two sides and a reference angle B. To find angle B, we shall apply the trigonometric ratio;
SinB = opposite/hypotenuse
SinB = 18/30
SinB = 0.6
By use of a calculator or table of values
B = 36.8698
Approximately, angle B = 36.87 degrees
Hi
perimeter of rectangle is : 2 length+2 width .
to progress in math, you must practice.
So , I let you do the first one which is the esaiest.
48 ) V147+ V147 + V108+V108 = 2V147 +2V108 = 2 ( V147+V108)
We have the perimeter of a base P = 20".
We have five congruent rectangles that together form a large rectangle
20" × 6".
The Lateral Area:
L.A. = 20 in · 6 in = 120 in²
All estimating problems make the assumption you are familar with your math facts, addition and multiplication. Since students normally memorize multiplication facts for single-digit numbers, any problem that can be simplified to single-digit numbers is easily worked.
2. You are asked to estimate 47.99 times 0.6. The problem statement suggests you do this by multiplying 50 times 0.6. That product is the same as 5 × 6, which is a math fact you have memorized. You know this because
.. 50 × 0.6 = (5 × 10) × (6 × 1/10)
.. = (5 × 6) × (10 ×1/10) . . . . . . . . . . . by the associative property of multiplication
.. = 30 × 1
.. = 30
3. You have not provided any clue as to the procedure reviewed in the lesson. Using a calculator,
.. 47.99 × 0.6 = 28.79 . . . . . . rounded to cents
4. You have to decide if knowing the price is near $30 is sufficient information, or whether you need to know it is precisely $28.79. In my opinion, knowing it is near $30 is good enough, unless I'm having to count pennies for any of several possible reasons.