Answer:
43 miles/hr
Step-by-step explanation:
Use a conversion factor from km to miles while keeping track of your units:
70 km/hr x 0.62 miles/km = 43 miles/hr
4(5x + 7) = 128
First, I'd do distributive property and get:
20x + 28 = 128
Then, subtract 28 from each side.
20x = 100
Next, I'd divide 100 by 20 = 5
x = 5
4 *(5(5) + 7) = 128
5 * 5 = 25
4 * (25 + 7)
4 * 32 = 128
Therefore, the perimeter = 2l + 2w
l = 4
w = 5x + 7
BUT we know that x = 5
w = 5(5) + 7 = 32
2(4) + 2(32)
8 + 64 = 72
Therefore, the perimeter would be 72 inches.
So -5x=-50
multiply both sides by -1
5x=50
divide by 5
x=10
check
-5 times 10=-50
-50=-50
check
3.46 to the nearest tenth is 3.5
6 is greater than 5, and so you round up
3.5 is your answer
hope this helps
