The common way of transforming the general form to the standard form is by using the completing the square method. But there is also a neat shortcut to knowing the h, k and r values right away.
The general formula is:
x²+y²+Dx+Ey+F = 0
x² + y² + (-2h)x + (-2k)y + (h²+k²-r²) = 0
Solving for h:
-2h = 42
h = -21
Solving for k:
-2k = 38
k = -19
Solving for r:
-47 = (-21)² + (-19)² - r²
r = √849
Standard form of given circle is:
(x+21)² + (y+19)² = 849
Answers:
1) B
2) B
3) B
4) D
let assume x percent of 150 is 39
so
150 × x % = 39
150 × x/100 = 39
x = 39×100/150 = 26 % answer
Answer:
Step-by-step explanation:
take 23 degree as reference angle
using tan rule
tan 23=opposite/adjacent
0.42=25/x
x=25/0.42
x=59.52
x=60
Answer:
2.95
Step-by-step explanation:
All you have to do is the reverse operations. Divide 21.9 by 2 then subtract it by 8.
Answer:
Step-by-step explanation:Rectangles have 4 sides--2 = lengths and 2 = widths, so perimeter = 2l + 2 w = 2(l + w).
l + w = (2x - 1) + (x + 3) = 3x + 2. Then double with distributive property P = 2(3x + 2)
P = 6x + 4
You could also do distributive property twice: 2(2x - 1) + 2(x + 3) = 4x - 2 + 2x + 6 = 6x + 4.
