Answer:
C
Step-by-step explanation:
Quadratic formula is used only to solve the quadratic equations .
Means the equation of the form

In this the x^2 part is must because that only makes the equation a quadratic.
Looking at the four options given to you , only the option C has the missing x^2 term, which makes it a linear equation and hence the quadratic formula cannot be applied there .
So the right option for your question with the quadratic formula is
option
C
As the question states, let r be the number of hours worked at the restaurant, and y be the number of hours of yard work.
We know that she can only work a maximum of 15 hours per work total, and that at she must work at least 5 hours in the restaurant.
Therefore:
r + y ≤ 15
r ≥ 5
We also know that she wants to earn at least 120 dollars, earning $8/hr in the restaurant and $12/hr in the yard:
8r + 12y ≥ 120
What is the maximum of hours Lia can work in the restaurant and still make at leas 120 hours?
Lia's parents won't let her work more than 15 hours, so we know that the answer won't be higher than 15.
If she worked all 15 hours in the restaurant, she would make 8*15 = 120.
The maximum number of hours she can work in the restaurant is therefore 15 hours
What is the maximum amount of money Lia can earn in a week?
Lia has to work a minimum of 5 hours in the restaurant. She makes more money doing yard work, so she should devote the rest of her available work hours to yard work.
That means that, given her 15 hour work limit, she will maximize her income by working 5 hours in the restaurant and 10 hours in the yard.
5*8 + 10*12 = 40 + 120 = 160
The most she can make is 160 dollars, working 5 hours in the restaurant and 10 hours in the yard
Let's assume the number be x.
So, sum of a number and 10 can be written as x+10.
Now the given statement is "One half of the sum of a number and 10 ".
So, one half of x+10 can be written as 
Answer:670
Step-by-step explanation:
200 + 500 - 30 =
700-30
670