The area of the parallelogram is 30% of the area of the trapezium.
work out the missing height of the parallelogram.
remember formula for area of trapezium= 72 (a +b) xh
10 cm
16 cm
19 cm
5 cm

You start off with the coefficient (or number that stands alone) by doing the inverse operation, if it's being added you subtract it on both sides. Then, you do the inverse operation of the number with a variable such as multiplication or division. When doing that step you should be left with the variable and the equal sign with the final answer.