(b)+(b+45)=215
b = # of boys
there are 45 more girls than boys and 215 students total.
minus 45 on both sides leaving you with
(b)+(b)=170
combine like terms leaving you with
2b=170
divide both sides by 2
b=85
there were 85 boys
85+45=130
(the 45 for the # of girls more than boys)
there were 130 girls.
Ew. Composition of functions. Ok, f(g(x)) is what that fancy notation means. So, you would take g(x) & substitute that into wherever x is in f(x).
So we get something crazy like
f(x)= 4 - (.5x - 2)^2
Now, we foil out the squared quantity:
f(x)= 4 - (.25x^2 - x - x + 4)
Can you believe they call that simplification?
f(x)= 4 - .25x^2 + 2x -4
Almost there...
f(x)= -.25x^2 + 2x
Hope this helps!
The inverse of a function will also be a function if it is a One-to-One function. This means, if each y value is paired with exactly one x value then the inverse of a function will also be a function.
Option C gives us such a function, all x values are different and all y values are different. So inverse of function given in option C will result in a relation which will also be a function.
In all other options, y values are being repeated, which means they are not one to one functions.
So, the answer to this question is option C
We presume you want to find values of x that make this true.
Subtract the right side and factor:

Once you have factors whose product is zero, you can find the values of x that make those factors zero. A product can only be zero if one or more contributing factors is zero.
To solve 2x-5=0, you can add 5 then divide by 2:
... 2x -5 = 0
... 2x = 5
... x = 5/2
Answer:
Hard to calculate first one is -1/2
Next one is 2.5/1.5 or 2 its hard to tell because of line (not clear)
Next one is -1/2 I think the numbers are small.
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