Answer:
x = 1/2 y = -1/3
Step-by-step explanation:
Split it into 2 equations:
10x-9y=8
and
21y+15x=0.5
10x - 9y = 8
Step 1: Divide both sides by 10:
x = (8+9y)/(10)
Substitute x = (8+9y)/(10) into 21y+15x=0.5 :
21y + (3(8+9))/(2) = 0.5
Solve for y
<u>y= -1/3</u>
Substitute y= -1/3 into x = (8+9y)/(10)
<u>x = 1/2</u>
<u />
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]
the least common multiple is 1,020 :)
Answer:
y=x+5
Step-by-step explanation:
Answer:
72
Step-by-step explanation:
<em>Since the ratio of blue jays to robin's was 6 to 7 then if there were 84 robins how many blue jays were there.</em>
<em>6 to 7 can also be express as 6/7</em>
<em>Thus, we can set up a proportion</em>
<em>6/7 = x/84</em>
<em>Now, we have to solve for x</em>
<em>x = 72</em>
<em>Hence, if there were 84 robin there would be 72 blue jays.</em>
<em />
<u><em>~lenvy~</em></u>
