What is the value of x in the equation 1/5x- 2/3y = 30, when y = 15?
4
8
80
200

The answer is 200.

Step-by-step explanation:

1/5x - 2/3y = 30

(y = 15)

1/5x - 2/3(15) = 30

(Since y is equal to 15)

1/5x - 10 = 30

1/5x = 30 + 10

1/5x = 40

x = 40 x 5

x = 200

If you have any doubts, you can ask me and I will try to answer you.

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

true !

step-by-step explanation: