Given quadrilateral ABCD, with A = 4x - 57 and C = x + 3, what value of x ensures that ABCD is a parallelogram?

how did you get x=20

To determine the value of x that ensures ABCD is a parallelogram, we need to examine the properties of a parallelogram.

One key property of a parallelogram is that opposite sides are parallel. This means that the slopes of AB and CD must be equal.

Let's find the equations of lines AB and CD based on the given coordinates of points A and C.

The slope of a line can be found using the formula: slope = (y2 - y1) / (x2 - x1)

Using the coordinates of points A and C, we can find the slopes of AB and CD.

For AB, let's consider points A(4x - 57, y) and B(? , ? ).

The slope of AB is given by: slope(AB) = (y - (4x - 57)) / (x - ?)

Similarly, for CD, let's consider points C(x + 3, y) and D(? , ? ).

The slope of CD is given by: slope(CD) = (y - (x + 3)) / (x - ?)

Since opposite sides of a parallelogram are parallel, the slopes of AB and CD must be equal.

Therefore, we can set up the equation:

(y - (4x - 57)) / (x - ?) = (y - (x + 3)) / (x - ?)

To solve for x, we need to match the y-values on both sides of the equation.

Let's set y = 0 and solve for x:

(0 - (4x - 57)) / (x - ?) = (0 - (x + 3)) / (x - ?)

Simplifying the equation further will allow us to find the value of x that ensures ABCD is a parallelogram.

recall the properties of parallelogram,,

one of the properties of a parallelogram is that the opposite angles are congruent/equal,, since you are given angles A and C, and they are opposite, equate them to get x:
4x - 57 = x + 3
combining similar terms,
4x - x = 57 + 3
*when transposing terms to other side of equation, the sign becomes the opposite,, that's why x (from right side) when transposed to left side becomes -x, and -57 becomes 57 after transposing,, simplifying this,
3x = 60
x = 20

hope this helps. :)