Answer:
See below.
Explanation:
So we have the two functions:
![f(x)=8x-5\text{ and } g(x)=9-2x](https://img.qammunity.org/2021/formulas/mathematics/high-school/sb21zcrxlqedyuls24c7dsn1bibvi6sfwl.png)
And we want to find:
![(f\circ g)(x)\text{ and } (g\circ f)(x)](https://img.qammunity.org/2021/formulas/mathematics/high-school/dfcqbmfx3b9raks70f40am12yje23pj49u.png)
1)
Recall that:
![(f\circ g)(x)](https://img.qammunity.org/2021/formulas/mathematics/high-school/eq320f057jfwvxcv5trvzl551czepjm4nq.png)
is the same as:
![=f(g(x))](https://img.qammunity.org/2021/formulas/mathematics/high-school/cnvvkq36fiqdr10fc07uczmhp5qlatptzi.png)
Thus, we can substitute g(x):
![=f(9-2x)](https://img.qammunity.org/2021/formulas/mathematics/high-school/wdwfpupd6cc5huwvgucu8zehevqjdtb9wf.png)
And substitute that into f(x):
![f(x)=8x-5\\f(9-2x)=8(9-2x)-5](https://img.qammunity.org/2021/formulas/mathematics/high-school/dvmznddqsevgsfj67rak9btzbik70205f1.png)
Distribute:
![=72-16x-5](https://img.qammunity.org/2021/formulas/mathematics/high-school/x8pmxdisobw52q7450edjg1wd66qbvr5ib.png)
Subtract and simplify:
![=67-16x\\=-16x+67](https://img.qammunity.org/2021/formulas/mathematics/high-school/c7tzo3a0lsh2uij85nhsoozmwoalaspcz0.png)
Thus:
![(f\circ g)(x)=-16x+67](https://img.qammunity.org/2021/formulas/mathematics/high-school/fa0x0ssv0x343rl3zevmq7xs9o9zmh57hy.png)
2)
Similarly:
![(g\circ f)(x)=g(f(x))](https://img.qammunity.org/2021/formulas/mathematics/high-school/xs85xcosw6ti3pppyd567m8w4zy7a07m0y.png)
Substitute f(x):
![g(f(x))=g(8x-5)](https://img.qammunity.org/2021/formulas/mathematics/high-school/y6wqxeqdl9tpq23drk201lkc33yxzufihi.png)
Substitute:
![g(8x-5)=9-2(8x-5)](https://img.qammunity.org/2021/formulas/mathematics/high-school/773z6stw3bmp3wg4jehfp2xznpw7gfuisg.png)
Distribute:
![=9-16x+10](https://img.qammunity.org/2021/formulas/mathematics/high-school/2a4pip6t7zl348500ms07xx7845ha76trg.png)
Simplify:
![=-16x+19](https://img.qammunity.org/2021/formulas/mathematics/high-school/psf1blp14sp1sqvtbm56d1nzz97905x3e3.png)
Therefore:
![(g\circ f)(x)=-16x+19](https://img.qammunity.org/2021/formulas/mathematics/high-school/vfx5u2puic27s352m4izaad614ov89vtvp.png)