First we need to find the the answer to both the square root of 49 and 9.
The "square root" is a term referring to a number, multiplied by itself (x • x) would be = to your square root.
So for example: Square root of 16 = 4 because 4*4=16
So lets get out numbers:


Now you multiply 3*7 (or 7*3) and you get 21.
Final answer: 21
P=2(L+W)
l=x+7
w=x
P=2(x+7+x)
P=2(2x+7)
P=4x+14
hast to be greater than 154
P>154
4x+14>154
minus 14 both sides
4x>140
divide 4
x>35
It might be 31 if you add all the numbers together but I'm not positive.
The answer would be 1.40. The 3 significant figure are 1.39 and it wants us to round so we look at the 8 in 1.3981 and since 8 > 5 we know to round up.