Answer:
x^2 + y^2 + 16x + 6y + 9 = 0
Step-by-step explanation:
Using the formula for equation of a circle
(x - a)^2 + (y + b)^2 = r^2
(a, b) - the center
r - radius of the circle
Inserting the values given in the question
(-8,3) and r = 8
a - -8
b - 3
r - 8
[ x -(-8)]^2 + (y+3)^2 = 8^2
(x + 8)^2 + (y + 3)^2 = 8^2
Solving the brackets
( x + 8)(x + 8) + (y +3)(y+3) = 64
x^2 + 16x + 64 + y^2 + 6y + 9 = 64
Rearranging algebrally,.
x^2 + y^2 + 16x + 6y + 9+64 - 64 = 0
Bringing in 64, thereby changing the + sign to -
Therefore, the equation of the circle =
x^2 + y^2 + 16x + 6y + 9 = 0
Answer: F=140
Step-by-step explanation:
720=(x-60)+(x-40)+(x-20)+130+120+110
720-130-120-110=3x-120
360=3x-120
360+120=3x
480=3x
480/3=x
160=x
F=160-20
Next problem
102+31+x=180
133+x=180
x=180-133
x=47
Answer:
kilometers per hour.
Step-by-step explanation:
We have been given an 
, which describes the number of kilometers y that a van travels in x minutes. We are asked to to find the constant speed of the van in terms of hours.
We can see that van travel 
kilometers in x hours. To find the constant speed of van, we will substitute 
in our given equation as:
Since van travels 
kilometers in one hour, therefore, constant speed of van is kilometer per hour or 
kilometers per hour.
Answer:
8. 504ft²
9. 4970yd² (rounded to 3 s.f.)
Formulas (For easy reference):
Area of rectangle = length × breadth
Area of circle = pi×r×r
Circumference of circle = pi×r×2
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Step-by-step explanation:
8. You know a box has 6 sides, and there are 3 types of surfaces that are different from each other, and you have to multiply each side by 2 cus there are the front and backside (You can draw the box with its dimensions to see the 3 types of surfaces and why I multiplied by 2):
(2×12×6) + (2×12×10) + (2×6×10) = 144 + 240 + 120
= 504ft²
9. The net of a cylinder contains two circles of radius 24yd and one long sheet to wrap around the circles with the length that is the circumference of the circle (so that it can wrap around the two circles) and a width which is the height of the cylinder (9yd).
2 Circles = 2×pi×24×24
= 1152pi
Long sheet = 9×24×2×pi
= 432pi
Now we can add all of them together:
432pi+1152pi = 1584pi
= 4970yd² (rounded to 3 s.f.)
