+130515 As x approaches 4 from the rght side, this will approach negative infinity. To see why, when x = 4 + 10-n , the first term will be hugely negative as n gets larger and larger, and will "overpower" the second term which will only approach about .602 as n gets larger and larger.
As x assumes larger and larger values in the direction of infinity, the graph will appproach + infinity, because both terms grow without bound......but, it will do so very slowly......
Here's a graph......https://www.desmos.com/calculator/6jgfncj9kx
+130515 x^2+3x<28 subtract 28 from each side
x^2 + 3x - 28 < 0 factor
(x + 7) (x - 4) < 0
Our answers will come from either these two invervals {- ∞, -7) and (4, ∞ )
Or, this interval (-7 , 4)
Let's pick 0 in the last interval and test it in the inequality
(0 + 7) ( 0 - 4) < 0 ???
(7) (-4) < 0 ???
-28 < 0 and this is true
So......the answer is x = (-7 ,4)
Here's a graph of y = x^2 + 3x - 28 ..... https://www.desmos.com/calculator/rq4hlo0pr0
Notice that the graph is < 0 on the interval (-7, 4)
