<h2>The awnser to your question is -42. Hope this helps!</h2>
-Ella
Answer:

Step-by-step explanation:
![\frac{15}{\sqrt{31} - 4}\\\\=\frac{15}{\sqrt{31} - 4} \times \frac{\sqrt{31} + 4}{\sqrt{31}+ 4} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ rationalizing \ the \ denominator \ ]\\\\=\frac{15( \sqrt{31} + 4 )}{(\sqrt{31})^2 - (4)^2} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ (a-b)(a+b) = a^2 - b^2 \ ]\\\\=\frac{15 ( \sqrt{31} + 4)}{31 - 16}\\\\=\frac{15 (\sqrt{31} + 4)}{15}\\\\= \sqrt{31} + 4](https://tex.z-dn.net/?f=%5Cfrac%7B15%7D%7B%5Csqrt%7B31%7D%20-%204%7D%5C%5C%5C%5C%3D%5Cfrac%7B15%7D%7B%5Csqrt%7B31%7D%20-%204%7D%20%5Ctimes%20%5Cfrac%7B%5Csqrt%7B31%7D%20%2B%204%7D%7B%5Csqrt%7B31%7D%2B%204%7D%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%20%20%5B%20%20%5C%20rationalizing%20%5C%20the%20%5C%20denominator%20%5C%20%5D%5C%5C%5C%5C%3D%5Cfrac%7B15%28%20%5Csqrt%7B31%7D%20%2B%204%20%29%7D%7B%28%5Csqrt%7B31%7D%29%5E2%20-%20%284%29%5E2%7D%20%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%5C%20%20%5C%20%5C%20%5C%20%5B%20%5C%20%28a-b%29%28a%2Bb%29%20%3D%20a%5E2%20-%20b%5E2%20%5C%20%5D%5C%5C%5C%5C%3D%5Cfrac%7B15%20%28%20%5Csqrt%7B31%7D%20%2B%204%29%7D%7B31%20-%2016%7D%5C%5C%5C%5C%3D%5Cfrac%7B15%20%28%5Csqrt%7B31%7D%20%2B%204%29%7D%7B15%7D%5C%5C%5C%5C%3D%20%5Csqrt%7B31%7D%20%2B%204)
1/2 (a+b)h
1/2 (a+16)14=132
8×14=112
14÷2=7
132-112=20
20÷7 =2.857142857
so then a= 2.86 (3sf)
For more questions like that turn it into equation the make a subject of formula
19.625cm squared because you have to divide the diameter by 2 to get the radius.
area of circle=pi times radius times radius
=3.14 times 2.5 times 2.5
=19.625cm squared
Answer:
The answer is "am irrational number"