5(11x-5)=85
55x-25=85
+25 +25
55x=110
---- -----
55 55
x = 2
7x+12+63=180
8x+12=180
Subtract 12 from both sides
8x= 168
=c=21
10x-40=50
Add 40 to both sides
10x=90
X=9
4x+72+2x-12=180
6x +60 =180
Subtract 60 from both sides
6x=120
X=20
Answer:930
Step-by-step explanation:
The answer in itself is 1/128 and here is the procedure to prove it:
cos(A)*cos(60+A)*cos(60-A) = cos(A)*(cos²60 - sin²A)
<span>= cos(A)*{(1/4) - 1 + cos²A} = cos(A)*(cos²A - 3/4) </span>
<span>= (1/4){4cos^3(A) - 3cos(A)} = (1/4)*cos(3A) </span>
Now we group applying what we see above
<span>cos(12)*cos(48)*cos(72) = </span>
<span>=cos(12)*cos(60-12)*cos(60+12) = (1/4)cos(36) </span>
<span>Similarly, cos(24)*cos(36)*cos(84) = (1/4)cos(72) </span>
<span>Now the given expression is: </span>
<span>= (1/4)cos(36)*(1/4)*cos(72)*cos(60) = </span>
<span>= (1/16)*(1/2)*{(√5 + 1)/4}*{(√5 - 1)/4} [cos(60) = 1/2; </span>
<span>cos(36) = (√5 + 1)/4 and cos(72) = cos(90-18) = </span>
<span>= sin(18) = (√5 - 1)/4] </span>
<span>And we seimplify it and it goes: (1/512)*(5-1) = 1/128</span>
Answer: 8.3 minutes
Step-by-step explanation:
1 mile is to 1.60934km so 93 million miles is:
= 93 * 1.609
= 149,637,000 km
Travelling at 300,000 km per second, the number of seconds it takes is:
= 149,637,000/300,000
= 498.79 secs
In minutes this is:
= 498.79/60
= 8.3 minutes