Answer:
tan(2u)=[4sqrt(21)]/[17]
Step-by-step explanation:
Let u=arcsin(0.4)
tan(2u)=sin(2u)/cos(2u)
tan(2u)=[2sin(u)cos(u)]/[cos^2(u)-sin^2(u)]
If u=arcsin(0.4), then sin(u)=0.4
By the Pythagorean Identity, cos^2(u)+sin^2(u)=1, we have cos^2(u)=1-sin^2(u)=1-(0.4)^2=1-0.16=0.84.
This also implies cos(u)=sqrt(0.84) since cosine is positive.
Plug in values:
tan(2u)=[2(0.4)(sqrt(0.84)]/[0.84-0.16]
tan(2u)=[2(0.4)(sqrt(0.84)]/[0.68]
tan(2u)=[(0.4)(sqrt(0.84)]/[0.34]
tan(2u)=[(40)(sqrt(0.84)]/[34]
tan(2u)=[(20)(sqrt(0.84)]/[17]
Note:
0.84=0.04(21)
So the principal square root of 0.04 is 0.2
Sqrt(0.84)=0.2sqrt(21).
tan(2u)=[(20)(0.2)(sqrt(21)]/[17]
tan(2u)=[(20)(2)sqrt(21)]/[170]
tan(2u)=[(2)(2)sqrt(21)]/[17]
tan(2u)=[4sqrt(21)]/[17]
Answer:
x=9
Step-by-step explanation:
Looking at the diagram, we see that four angles are formed by the intersection of two lines. The angles highlighted in blue and green are therefore, vertical angles. We know that vertical angles have equal angle measures meaning that in this case, the measure of the blue angle is equal to the measure of the green angle. Using this, we can now solve for x:
7x+49=2x+94
7x-2x=94-49
5x=45
x=45/5
x=9
Answer:
d = 
Step-by-step explanation:
1) To solve for d, isolate it in the equation. So, to get rid of the 
with the d, add 
to both sides.
Thus, d = .
Answer:
$190 is the answer
minus $5 from $97.50 and add that number to $97.50
Answer:
He has 4 more to hang
Step-by-step explanation:
13 total; you must add the 5 he already hung in the morning plus, the 4 he hung in the afternoon; leaving you with 4 because 5 plus 4 is 9. 13 minus 9 is 4.
