Usually when you try and find the area you would multiply but you don't have one of the numbers to multiply, so what is the oppisite of multiplication? Divison. You would divide the area by the highth. so it would be 4.5 divided by 1.8. 4.5 divided by 1.8 equals 2.5. And to make sure your answer is correct you would multiply 1.8 times 2.5 wich does equal 4.5. The highth is 1.8, the Length is 2.5, and the are is 4.5
