Answer:
Yes, SAS theorem. Angle ACB and Angle ECD are congruent because of the vertical angles theorem.
Step-by-step explanation:
Answer:
230 cm^2
Step-by-step explanation:
The area of each parallelogram face is ...
A = bh = (8 cm)(3 cm) = 24 cm^2
The area of the two rectangular faces shown is ...
A = (area of top face) + (area of right side face)
A = (8 cm)(7 cm) +(5 cm)(7 cm) = 91 cm^2
The three faces we have figured the area of are half the total area, since there are three more faces exactly the same size. Then the total area of the figure is ...
total surface area = 2(24 cm^2 +91 cm^2) = 230 cm^2
_____
Of course, the area of a rectangle is given by A=L·W, where L and W represent the length and width of the rectangle.
Answer:
centre = (- 3, - 2) , radius = 1
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
Given
x² + 6x + y² + 4y + 12 = 0 ( subtract 12 from both sides )
x² + 6x + y² + 4y = - 12
Use the method of completing the square on the x and y terms
add ( half the coefficient of the x/ y terms )² to both sides
x² + 2(3)x + 9 + y² + 2(2)y + 4 = - 12 + 9 + 4
(x + 3)² + (y + 2)² = 1 ← in standard form
with centre = (- (- 3), - (- 2)) and r² = 1, that is
centre = (- 3, - 2) and radius = 1
