First we use sin(a+b)= sinacosb+sinbcosa
and cos(a+b)=cosa cosb -sinasinb
tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)
and sin(x+pi/2) = sinxcospi/2 + sinpi/2cosx =cosx,
<span>cos(x+pi/2) = cosxcospi/2- sinxsinpi/2= - sinx,
</span> because <span>cospi/2 =0, </span>and <span>sinpi/2=1
</span><span>=tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)= cosx / -sinx = -1/tanx = -cotx
</span>from where <span>tan(x+pi/2)=-cotx</span>
Tower A is: 2411092
Tower B is: 1630312
A)
<span>|x + y = 5 </span>
<span>|2x - y = 7; </span>
<span>b) </span>
<span>|2x + y = 5 </span>
<span>|x - y = 2 </span>
<span>c) </span>
<span>|3x + y = 6 </span>
<span>|4x - 3y = -5 </span>
<span>d) </span>
<span>|1/(x - 1) = y - 3 </span>
<span>|x - y = -2 </span>
<span>e) </span>
<span>|(9x + 4y)/3 - (5x - 11)/2 = 13 - y </span>
<span>|13x - 7y = -8 </span>
<span>Answer: </span>c<span> and </span>e<span> has solution (1; 3)</span>
D because it helps better and explains better and makes most sense
Answer:
$51.1
Step-by-step explanation:
If Joe spent 15/22 of his pocket money in a story book which costs $75, he had $51.1 at first.
15/22 of 75 = 51.1363636364 or 51.1
