Answer:
Sales tax = 7%.
Step-by-step explanation:
Let x be the percent of sales tax.
We have been given that Lisa buys a television for $4185. The sales tax is $292.95.
We need to figure out x such that x percent of 4185 equals to 292.95. Let us represent this information in an equation.
Let us multiply both sides of equation by 100.


Therefore, sales tax is 7%.
Let us cross check our answer by calculating 7% of 4185.



We can see that 7% of 4185 is 292.95. Hence, sales tax is 7%.
Answer:C) x2 + y2 =45
Step-by-step explanation:
The equation of a circle in standard form is (x-h)2+(y-k)2=r2.
Since you know the center is (0,0), you can sub this is value in for h and k, then use the point (3,6) to sub in for x and y and you will find r2 =45. Hope that helps :)
<span>Inflection points are where the function changes concavity. Since concave up corresponds to a positive second derivative and concave down corresponds to a negative second derivative, then when the function changes from concave up to concave down (or vise versa) the second derivative must equal zero at that point. So the second derivative must equal zero to be an inflection point. But don't get excited yet. You have to make sure that the concavity actually changes at that point.</span>