Which value of x makes this inequality true?
X + 9 < 4x

We want to get out x's together on the right side of the inequality.

So, subtract x from both sides to get 9 < 3x.

Now divide both sides by 3 and we get 3 < x.

I personally like to have my variables on the left so we can move the 3 to the left and the x to the right but if we do that, we have to switch the inequality sign.

So we can rewrite this as x > 3.

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this

i dont know

step-by-step explanation: