Answer:
Roughly 18,000
Step-by-step explanation:
When you need to do rough mental math, you can do something like 720 vs 25 or 30 which is pretty simple to do in your head.
If you are very proficient in mental math, you can do something like 720 * 25, which is harder, but if you know the tricks, you can do this quickly.
720 * 25
Multiply 25 by 7.
175
Add two zeros.
17,500
Multiply 25 by 2
50
Add a zero.
500.
17500 + 500 = 18000
Answer: The depth of the snow has changed .4 inches. This is because it has melted in the warm weather. You can find the difference, by subtracting 1.6 from 2.
Step-by-step explanation:
2 - 1.6= .4 .4 would be your answer
Hope it helps!!!!
Answer:
x²-8x-1=0
comparing above equation with ax²+bx+c=0
a=1
b=-8
c=-1
x=

=(--8+-√(64-4×1×-1)/2×1
=8+-√(64+4)/2
taking positive
x=(8+√68)/2=2(4+√17)/2=4+√17
taking negative
x=(8-√68)/2=2(4-√17)/2=4-√17
2. 3. 5. are correct
1. and 4. are actually interchanged
The first bullet is the answer