Answer:
and 
Step-by-step explanation:
when you solve for r in the given equation, you need to apply the square root property, which gives positive and negative answers (both should therefore be considered):

then you need to include these two possible solutions:
and 
(-5a)(-3a ²)
=
15a³
-5 x -3 = 15 ( negative times negative = positive)
a x a² = a³ ( when multiplying exponents, you add the exponents together )
Solution:
we are given that
The magnitudes of the moon and Sirius are -12.5 and -1.44 respectively.
we have been asked to find approximately how many times is the moon brighter than Sirius?
The word magnitude is used by the scientist to describe the brightness of moon/star/object etc.
So we can find the brightness by dividing the given values. so we get

Hence we can say
The moon is 8.68 times brighter than Sirius.
Answer:
I hope this answer helps you
The answer is 3.40 since you rounded to the hundredths place and not the tenths.