I assume you mean the product of mixed numbers,
3 1/2 × 3 1/2
If we write this as
(3 + 1/2) × (3 + 1/2) = (3 + 1/2)²
we can use the identity
(a + b)² = a² + 2ab + b²
so that
3 1/2 × 3 1/2 = 3² + (2 × 3 × 1/2) + (1/2)²
3 1/2 × 3 1/2 = 9 + 3 + 1/4
3 1/2 × 3 1/2 = 12 1/4
Alternatively, we can first write 3 1/2 as a mixed number:
3 + 1/2 = 6/2 + 1/2 = (6 + 1)/2 = 7/2
Then
3 1/2 × 3 1/2 = 7/2 × 7/2 = (7 × 7) / (2 × 2) = 49/4
and
49/4 = (48 + 1)/4 = ((4 × 12) + 1)/4 = 12 + 1/4
You need to make a series of equations from what you are given first. I am going to use the first letter of each of the names to represent the length of that persons wire.
1/2s=2/5d
3c=s
s+d+c=6 ft
Okay. Now you can combine the first two equations knowing what s equals:
1/2(3c)=2/5d
d=15c/4
Now you have d=15c/4 and s=3c, so you can replace d and s in the third equation.
3c+15c/4+c=6
Then solve for c and plug it into the equation 3c=s to find the length of sarah's wire.
1 2 3
1 2 3 1 2 3 1 2 3
123 123 123 123 123 123 123 123 123
3 3 3 3 3 3 3 3 3
3(9)
27
Answer:
9 miles
Step-by-step explanation:
use Pythagoras theorem
15 squared - 12 squared = 81
square root of 81 is 9
