help!!!Its math?

Question

1.) Given f(x)=l3x-6l, find(0)-f(3)

2.) given g(x+deltax)-g(x) / delta x for g(x)=x^2=3x-1

3.)Which of the following equations expresses y as a function of x?

Choices
A.) 3y+2x-9=17
B.) 2x^2 (y)+x=4y
C.)Both a and b
D.) Neither and a b
E.) 3y^2 -x^2=5

Answer 1

1) You mean f(0) - f(3)? Just plug in x=0 to find f(0), then plug in x=3 to find f(3), and subtract the two.

2) Either you're missing the second half of this, or you worded it incorrectly.

3) Neither a nor b. A, B, and E give expressions that involve both x and y, but none of them show y in terms of x. If that was the case, we'd see "y = " on the left and terms that use only constants and x on the right side.

Answer 2

I have rewritten your questions as I think they were meant to be. If I'm wrong, then disregard answers.

1.) Given f(x)=l3x-6l, find f(0)-f(3)
f(0)= |0-6| = 6
f(3) = |3*3-6| =|9-6| = 3
Thus f(0)-f(3) = 6-3 = 3

2.) given g(x+deltax)-g(x) / delta x for g(x)=x^2+3x-1
Let delta x = h
Then g(x+h) = (x+h)^2 +3(x+h)-1 = x^2+2xh+h^2+3x+3h-1
So [g(x+h) -g(x)]/h = (2xh +3h+h^2)h = 2x+3+h

3.) If the equations A, B, and E are solved for y , then they would all would expres y as a function of x. As it is, however, none of them express y as a function of x. Answer D makes no sense whatsoever. Poor question.