Let L represent the ladder length, and x the distance the horiz. ladder reaches out from the wall. Then L = x + 3, where x is the distance of the bottom of the ladder from the wall when the top of the ladder is 9 ft. above the ground.
Consider the triangle formed by the hypotenuse (L, same as ladder length), the (vertical) side opposite the angle formed by the hypo. (with length 9 ft) and the horiz side (which we will call x). Then, according to the Pythagorean Theorem,
L^2 = x^2 + 9^2. But L = x + 3, and L^2 = x^2 + 6x + 9 = x^2 + 9^2. Solving this equation results in x=3. 6x + 9 = 9^2, or
6x + 9 = 81
6x = 72
x = 12
But L = x+3. So L=12+3, or L = 15 (feet).
Important notes:
3 sides 1 angle - COSINE RULE
2 sides 2 angle - SINE RULE
since, the question wants to find the length of BC. In the end we will have 3 sides and 1 angle and use cosine rule
formula of cosine rule:
a² = b² + c² - 2bc Cos A° (to find the length)
Cos A° = b² + c² - a² / 2bc ( to find the angle, if there is given three sides and have to find the angle)
So just substitute,
a² = 13² + 15² - 2(13)(15) Cos 95°
a = 20.6 or 21
Answer:
4 2/3 cm
Step-by-step explanation:
When we have area, it is the related to the scale factor by the scale factor squared
Area large/ area of small = 49/9
Take the square root
sqrt(49/9) = 7/3
The scale factor is 7/3 large to small
The small side is 2 cm
large 7 x cm
-------- = ------ = -----------
small 3 2 cm
Using cross products
7*2 = 3x
Divide by 3
14/3 = 3x/3
14/3 = the large side
4 2/3 cm
Answer:
50/50
Step-by-step explanation:
half the numbers are odd, half even, on a die, so its a 50/50 chance