On Saturday, Kelly borrowed $15 from her sister. The next day, she paid back $4. On Tuesday, she borrowed $9 more. How much money does Kelly now owe her sister?

20$ owed back

Step-by-step explanation:

Let's understand this sentence by sentence.

On Saturday, Kelly borrowed $15 from her sister. The next day, she paid back $4. On Tuesday, she borrowed $9 more. How much money does Kelly now owe her sister?

"On Saturday, Kelly borrowed $15 from her sister." That means that she owes 15 dollars to her sister right now.

"The next day, she paid back $4." That means that she is now 4$ less in debt. So in total, she is 11$ in debt now. (Is that actually real debt?)

"On Tuesday, she borrowed $9 more." That means that she owes even more money again. To be precise, 9$ more.

So 11$ + 9$ = 20$ owed

20$ owed at the end

guess at question:

a vertical line intersects the graph of g(x,y) = 0 at two points. what conclusion follows about the function f(x) implicitly defined by g(x,f(x)) = 0?

the domain of f(x) cannot include the x coordinate of any such vertical line.

informally, f(x) is not a function, and

g(x,y)=0 cannot be solved for y uniquely.

the relation r = {(x,y) such that g(x,y) = 0} is a function if

for all (a,b) ∊ r and (c,d) ∊ r, a=c implies b=d.

step-by-step explanation: