The height is 4.
6 is the given width at the top and because it’s a parallelogram, that means the bottom is equal to 6 as well. So that makes the base 6 units. The formula to find the area of a parallelogram is b x h and because you’re given two values, you just plug them into the formula and solve for the missing one. You’ll get 24 = 6 x h. You can solve this by dividing both sides by 6 and you’ll end up with h = 4.