She subtracted on the right side, when she should've added.
The answer is B
"Helen should have added 17 to both sides of the equation."
You know because if you round to the nearest whole number for these numbers, you will have 13 + 3 + 5, which you know is greater than 20.
Answer:
Step-by-step explanation:
Given
Required
Find h when P = 246
Substitute 246 for P
Collect like terms
Make h the subject
The inequality is 
because we start off with 95 pounds and then add on x more (x is some positive number). The expression 95+x is the total weight. We want this total weight to be less than or equal to 800. In other words, 800 is the highest we can go. Or put another way, we can have 800 or smaller.
To solve that inequality, subtract 95 from both sides and you end up with this inequality 
meaning that we can add up to 705 pounds of extra people or things to this elevator.
Answer: D
Step-by-step explanation:
To express this number in scientific notation, we want to move the decimal so that it goes past the first nonzero integer. In this case, we would move it to the right 8 times.
6.7×10⁻⁸
The only reason why the 8 is negative is because when you write the scientific notation in standard form, you will need to move the decimal to the left in order to get 0.000000067. Negative means moving to the left. Therefore, 6.7×10⁻⁸ is our correct answer.
