Answer:
Step-by-step explanation:
x² + 2x - 3 + y² = 5
Strategy:
Convert the equation to the centre-radius form:
(x - h)² + (y - k)² = r²
The centre of the circle is at (h, k) and the radius is r
.
Solution:
Move the number to the right-hand side.
x² + 2x + y² = 8
Complete the square for x
(Take half the coefficient of x, square it, and add to each side of the equation)
(x² + 2x + 1) + y² = 9
Complete the square for y
The coefficient of y is zero.
(x² + 2x + 1) + y² = 9
Express the result as the sum of squares
(x + 1)² + y² = 3²
h = -1; k = 0; r = 3
The centre of the circle is at 
The graph of the circle below has its centre at (-1,0) and radius 3.
Answer:
x=7 and y=-1
Step-by-step explanation:
X+Y=6 OR X=6-Y ...(1)
X-Y=8 ...(2)
substitue X=6-Y in (2)
(6-Y)-Y=8
6-2Y=8
-2Y=8-6
-2Y=2
Y=2/-2\Y=-1 ANS.
for x, substitute Y=-1 in (1) above
X-(-1)=8
X=8-1
X=7 ANS.
Answer:
263,870
Step-by-step explanation:
Answer:
437.4 meters squared
Step-by-step explanation:
7.2*4.5=32.4=b
3*4.5=13.5=h
b*h=a
32.4*13.5=437.4m^2
Answer:number of cupcakes sold is 13
Number of cookies sold is 27
Step-by-step explanation:
Let x represent the number of cupcakes that Jane sold.
Let y represent the number of cookies that Jane sold.
Each cupcake sold for $2.25 and each cookie sold for $0.50. At the end of the day, Jean had sold $42.75 worth of cookies and cupcakes.
This means that
2.25x + 0.5y = 42.75 - - - - - - - - - -1
she sold 40 cupcakes and cookies combined, it means that
x + y = 40
Substituting x = 40 - y into equation 1, it becomes
2.25(40 - y) + 0.5y = 42.75
90 - 2.25y + 0.5y = 42.75
- 2.25y + 0.5y = 42.75 - 90
- 1.75y = - 47.25
y = - 47.35/-1.75
y = 27
x = 40 - y
x = 40-27 = 13
.
