Answer:
C
Step-by-step explanation:
I did that test before we trusty meee
Answer: (99/13, 150/13)
Step-by-step explanation:
I'm too lazy to explain so here's a screen shot from desmos.
38: it's a right triangle
39:
area:


circumference:



Substitute 51/5x into

Substitute that into

Hope this helps. Answer should be correct. Unless your quadratic equation is wrongly stated.
If you distribute -4 through (5k-7), it equals -20k + 28. Then put on the other -2k on that side of the equals sign and you should have -22k + 28 = -2(9k+5) Then you need to distribute -2 through (9k+5) which equals -18k - 10. You then should have -22k+28=-18k-10. Add 22k to both sides to cancel it out, then you should have 28=4k-10. Add 10 to both sides to get the 4k by itself, which will be 38=4k, then divide both sides by 4 to get k by itself. 38/4 = 19/2. k = 19/2