As soon as I read this, the words "law of cosines" popped
into my head. I don't have a good intuitive feeling for the
law of cosines, but I went and looked it up (you probably
could have done that), and I found that it's exactly what
you need for this problem.
The "law of cosines" relates the lengths of the sides of any
triangle to the cosine of one of its angles ... just what we need,
since we know all the sides, and we want to find one of the angles.
To find angle-B, the law of cosines says
b² = a² + c² - 2 a c cosine(B)
B = angle-B
b = the side opposite angle-B = 1.4
a, c = the other 2 sides = 1 and 1.9
(1.4)² = (1)² + (1.9)² - (2 x 1 x 1.9) cos(B)
1.96 = (1) + (3.61) - (3.8) cos(B)
Add 3.8 cos(B) from each side:
1.96 + 3.8 cos(B) = 4.61
Subtract 1.96 from each side:
3.8 cos(B) = 2.65
Divide each side by 3.8 :
cos(B) = 0.69737 (rounded)
Whipping out the
trusty calculator:
B = the angle whose cosine is 0.69737
= 45.784° .
Now, for the first time, I'll take a deep breath, then hold it
while I look back at the question and see whether this is
anywhere near one of the choices ...
By gosh ! Choice 'B' is 45.8° ! yay !
I'll bet that's it !
Answer:
0.9 tons or 9 tons
Step-by-step explanation:
<u>For 1800 pounds</u>
1 ton = 0.0005 pounds
so
0.9 tons = 1800 pounds
<u>For 18000 pounds</u>
1 ton = 0.0005 pounds
so
9 tons = 18000 pounds
You can just do the inverse operation. 39 divied by 10 = 3.9
so 3.9 *10 =39
hope it helped
The distance formula to find the length of the sides... opposite sides equal it could be a rectangle or parallelogram all sides equal, square or rhombus adjacent equal, kite and then the slope is used to check angles if the product of the 2 lines in -1 the lines are perpendicular (right angle) the slopes of 2 lines are the same the sides are parallel. Hope it helps.
What is your question I will answer it if I can
