Rafael and Roger played tennis against each other 30 times. Each of the times they played, either Rafael won or Roger won. The ratio of the number of times Rafael won to the number of times Roger won is 7 : 3 Work out the number of times Rafael won.

where are the options?

step-by-step explanation:

$79500

step-by-step explanation:

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:

x=-7

step-by-step explanation:

x+3=-10

-10+3=-7

x=-7