The formula for rectangle area is A = l * w. This means that the Area of the rectangle is equivalent to the width and length (or height) of the rectangle.
Since we already know that the width is 4x, and the height is 7/3 x, we can plug these into the formula. Our formula now looks like A = 4x * 7/3 x.
We also know that x=6. Plugging in 6, for our x in the equation, we get A= 4(6) * 7/3 (6/1). I have put our 6 into fraction form since that is how we multiply fractions, numerator times numerator, and denominator times denominator. This leaves us with A = 24 * 42/3. We can divide 42 -: 3 to get our decimal value, which comes out to be 14.
Now all that is left to do is to multiply 24 * 14 to get our area.
A = 24 * 14 => A = 336