Math
posted by Dana .
1) A helium balloon is rising according to the function H(t) = 7x^2 + 5x  11 where h(t) is the height in meters after t seconds. Determine the average rates of increase of height from t=7 to t=23 seconds.
I tried
h(23)  h(7)

237
= * in this step i subbed it into the equation.
= 3599 + 319

16
It seems odd...
2) What is the end behaviour of
f(x) = 23x+4x^2

8x^2+5x11
I understand end behaviour..but can someone help rearrange the first equation?
3) 2^2x  4 (2^x) + 3 = 0
Solve for x.
This one I don't get at all.
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