What is the lcd of and -

again, let's take a peek to our denominators.

12 = 2*2*3

16 = 2*2*2*2

now, 2*2 is there in each number as factors, so we'll use it only once, not twice, after that we have a 3, a 2 and another 2.

33.5 unit²

it's a mixture of triangle and square.

draw a imaginary straight line across the figure from that line which has length of 3 units and now you can see the triangle and the square. Use the formula to find area of triangle and area of square and the sum of their area will be the area of this whole figure i.e 35.5 unit²