Step-by-step explanation:
the mean value is the sum of all values divided by how many values there are.
so,
(3 + -5 + 70 + -90 + -13) / 5 = -35/5 = -7
-7° F is the mean temperature of the 5 cities.
Are you sure the options are what u have written above? because sqrt of 5x=sqrt of 5x,
sqrt of 20x=2•sqrt of 5x,and sqrt of 80x= 4•sqrt of 5x..
-3(2x-4)+8x-8
-6x+12+8x-8
2x+4
x=2