Answer:
f(x)=x^2+9x-10
Step-by-step explanation:
<u>Standard Form of Quadratic Function</u>
The standard form of a quadratic function is:

where a,b, and c are constants.
The factored form of a quadratic equation is:

Where
and
are the roots or zeros of f, and a is constant.
We know the zeros of the function are 1 and -10. The function is:


Operating:

Joining like terms:

Since we are not given any more restrictions, we can choose the value of a=1, thus. the required function is:

X= weight of TV
y= weight of CD
3x+5y= 62.5
3x+ 2y= 52
You can either solve for a variable, or eliminate a variable by subtracting the second equation from the first:
3x + 5y = 62.5
-(3x+2y = 52)
0 + 3y = 10.5, so y = 10.5/3 or 3.5.
Now plug y= 3.5 back into any equation to get x:
3x + 5(3.5) = 62.5
3x + 17.5 = 62.5
3x = 45
x = 15
Always check work. Both equations should be true for x=15, y= 3.5
Answer:
the second one(20)
Step-by-step explanation:
If you pretend 20 is x, you solve the equation by pluging in x (20) into the equation and it gives you 70, 70 is what the big part is and 70+20 is 90, which is the size of a 90degree side.
4(20)-10
80-10
70
70+20=90
The answer to your question is -10