I'm sorry you need to be more clear I don't understand the question.
Answer:
You need to study to do good on those exams bud.
Answer: Variables
F and C are placeholders for numbers. They are called variables because they are allowed to vary, or change. If you change C then it affects F, and vice versa. If the values for the placeholders is not allowed to change, yet it holds a number, then it is considered a constant. In this case, we don't have constants or else the formula isn't too useful.
Answer:
$175
Step-by-step explanation:
$60÷3÷4 =5
$5 is the cost of one adult's food for one day.
$5×7×5
=$175
$175 is the cost of food consumed by 7 adults for 5 days.
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...
