You and your friend are selling magazine subscriptions for a fundraiser. After w weeks, you have sold (3w+8) subscriptions and your friend has sold (6w+6) subscriptions.

3w-2

Step-by-step explanation:

Given that, after w weeks you sold (3w+8) subscriptions and your friend sold (6w+6) subscriptions.

So, the difference between the number of subscriptions your friend has sold and you have sold after w weeks = (6w+6)-(3w+8)

=6w+6-3w-8

=3w-2

Hence, the required expression is 3w-2.

13

step-by-step explanation:

169-1=168

168-3=165

165-5=160

160-7=153

153-9=144

144-11=133

133-13=120

120-15=105

105-17=88

88-19=69

69-21=48

48-23=25

25-25=0

since it took 13times to completely subtract it hence its square root is 13