Answer:

since 5.46 is equal to 5.5...
I think the answer is the first one
Answer:
Step-by-step explanation:
4b+8=40
4b=32
b=8
To solve for a variable, you need to get it (x) by itself.
x² - 14 + 31 = 63 Add 31 to -14
x² + 17 = 63 Subtract 17 from both sides of the equation
x² = 46 Square root both sides
x =

Check your work by plugging in

for x and then

.

² - 14 + 31 = 63 Square

46 - 14 + 31 = 63 Subtract 14 from 46
32 + 31 = 63 Add
63 = 63

² - 14 + 31 = 63 Square

46 - 14 + 31 = 63 Subtract 14 from 46
32 + 31 = 63 Add
63 = 63
So,
x is
and 
.
Answer:
1/150000
Step-by-step explanation:
from km to cm you should multiply it by 100000
Here is one way to show that the left side is identical to the right side.

Throughout the entire process, the right hand side stayed the same. When working on identities, it's important to keep one side the same while you transform the other side.
Despite the two sides being identical when simplified, there is the issue of cos(x) being zero in the denominator on the left hand side. Be sure to account for this when forming the domain. No such issue occurs on the right hand side. For instance, the value x = pi/2 leads to a division by zero error when in radian mode. So if I was your teacher, I would revise the "for any value of x" and replace it with something along the lines of "for any x value in the domain".