The Answer Is 18
Order Of Operation laws says that you must do the parentheses first, 45x2.
45x2=90
The next thing you must do is divide 90 by 10 since division is before addition.
90/10=9
Now combine like terms.
9+9=18
The mean is not the same thing as median
mean=78+81+85+87=331
mean=331/4=82.75
median is the middle number, but you have a par set of numbers, so your median will be the middle numbers 78,81,85,87 , which are 81+85=166, 166/2=83
83 is your median
Answer:
x = -7 ±3i
Step-by-step explanation:
(x+7)^2+9=0
Subtract 9 from each side
(x+7)^2+9-9=0-9
(x+7)^2=-9
Take the square root of each side
sqrt((x+7)^2) = ±sqrt(-9)
We know sqrt(ab) = sqrt(a) sqrt(b)
x+7 = ±sqrt(-1) sqrt(9)
We know that sqrt(-1) is the imaginary number i
x+7 = ±i *3
x+7 =±3i
Subtract 7 from each side
x+7-7 = -7 ±3i
x = -7 ±3i