Answer:
Step-by-step explanation:
The total amount Rita spent is ...
(18.54x +23) +(25) = 18.54x +48 . . . total spent
__
When x=2, that is approximately ...
(18.5)(2) + 48 = 37 +48 = (40 -3) +(50 -2) = (40 +50) -(3 +2) = 90 -5 = 85
Rita spent about $85 if she bought 2 items.
_____
<em>Additional comment</em>
Estimation is often done using 1 significant figure. In this case, that would mean rounding the equation to 20x+50, so it would give a value of 90 when x=2.
An additional task when estimating is to estimate the error in the estimate. Here, using 20x+50 has an error of approximately 1.5x+2 (too high), so the error for 2 items will be about (1.5(2)+2) = 5. That is, the estimate of 90 is approximately 5 too high. Even this estimate has a remaining small error of 0.04x (too low).
Answer:
{ x | -3 <= x < +1 }
Step-by-step explanation:
We note that the graph occupies from x=-3 to x=+1, while -3 is a value included (endpoint is solid), and +1 is excluded (endpoint hollow).
Thus the domain is { x | -3 <= x < +1 }
Answer:
After 4 seconds, the ball is at 229 ft
Step-by-step explanation:
Here, we want to get the height of the ball at 4 seconds
What we have to do here is to substitute the value of t for 4 seconds in the equation
We have;
h = -16(4^2) + 121(4) + 1
h = -256 + 484 + 1
h = 229 ft
