The perimeter p of the rectangle equals 30. Find the value of X?

13

Step-by-step explanation:

The perimeter is calculated by multiplying the sum of width and height with 2

2*(4x-2+7x+9) = 300 solve inside the parenthesis

2*(11x+7) = 300 multiply inside the parenthesis with 2

22x + 14 = 300 subtract 14 from both sides

22x = 286 divide both sides by 22

x = 13

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

207/8 is the right