Answer:
r = √13
Step-by-step explanation:
Starting with x^2+y^2+6x-2y+3, group like terms, first x terms and then y terms: x^2 + 6x + y^2 -2y = 3. Please note that there has to be an " = " sign in this equation, and that I have taken the liberty of replacing " +3" with " = 3 ."
We need to "complete the square" of x^2 + 6x. I'll just jump in and do it: Take half of the coefficient of the x term and square it; add, and then subtract, this square from x^2 + 6x: x^2 + 6x + 3^2 - 3^2. Then do the same for y^2 - 2y: y^2 - 2y + 1^2 - 1^2.
Now re-write the perfect square x^2 + 6x + 9 by (x + 3)^2. Then we have x^2 + 6x + 9 - 9; also y^2 - 1y + 1 - 1. Making these replacements:
(x + 3)^2 - 9 + (y - 1)^2 -1 = 3. Move the constants -9 and -1 to the other side of the equation: (x + 3)^2 + (y - 1)^2 = 3 + 9 + 1 = 13
Then the original equation now looks like (x + 3)^2 + (y - 1)^2 = 13, and this 13 is the square of the radius, r: r^2 = 13, so that the radius is r = √13.
Pi/2 falls at 90 degrees on the unit circle, or 0,1. And since sin is the y value, sin (pi/2) = 1
I think the first one is 4 dollars
Because 30 divided by 4
Answer:
I didn't understood your question. But,
- Formula to find rate of interest=
<em>I×</em><em>1</em><em>0</em><em>0</em><em>/</em><em>P×</em><em>T</em>
If c = the cost of one table, the cost of all 25 tables before sales tax is 25·c
Since the sales tax is 5%, or 0.05, the sales tax for 25 tables is 25·c·0.05
Adding the sales tax to the original cost of the 25 tables can give you:
25·c + 25·c·0.05 = 1706.25
1.05·25·c = 1706.25
26.25·c = 1706.25
c =
= 65
so the refund for 5 tables would be 5*65 = $325
