y=mx+b A=xy; A=(pi)r^2; V=xyh; (-b= or - (b^2-4ac)^1/2)/2a ( actually read as negative b plus or minus the square root of b squared minus four ac, all divided by 2a....quadratic formula) This should get you, if you need more or this is not what you were looking for, let me know.
4a
2a - 5a = -3a
9a +8 -2a -3 -5a = 2a +5
2a x 3b = 6ab
2a-5
2a+5
since a=1a, 3a-1a=2a
2a
-2a - 4 = -16.8 -2a = -12.8 a = -12.8/-2 a = 6.4
2
-16A
2a+6b
6a to the second power minus 8ab + 2a
2a + 11a - 5a = 8a
(a - 2b)(2a - b)
(2a - 5). Take the value of a. Double it to get 2a Take away (subtract 5) to get 2a - 5