Answer:
D.
Step-by-step explanation:
A=2πrh+2πr2 is the equation, so now all you have to do is plug the numbers in. (also there's a calculator for this on google btw)
Answer:
C
Step-by-step explanation:
y-3=5(x-2) (rearrange this to be in slope- intercept from) (add 3 to both sides)
y = 5(x-2) + 3 (distribute parentheses)
y = x(5) - 2(5) + 3
y = 5x -10 + 3
y = 5x - 7
recall that for a line with gradient m, the gradient of the perpendicular line will be - (1/m)
hence in our case, our gradient of the original line is 5, hence the gradient of the perpendicular line is -1/5
From the choices, the only one that is consistent with this is C
i.e choice C:
5y + x = 25
5y = -x + 25
y = -(1/5) x + 5 ===> gradient of -1/5
Answer:
x = -1 and y = 18
Step-by-step explanation:
Given the system of equations
y + 8x = 10... 1
2y - 4x = 40 ... 2
From 1; y = 10-8x
Substitute into 2;
2(10-8x) - 4x = 40
20 - 16x - 4x = 40
20 - 20x = 40
-20x = 40 - 20
-20x = 20
x = -1
Recall that y = 10-8x
y = 10 - 8(-1)
y = 10 + 8
y = 18
therefore your answer is x = -1 and y = 18
We can see that revolving the region formed by intersecting 3 lines, we will get 2 cones that are connected their bases.
Volume of the cone V=1/3 *πr²*h
1) small cone has r=5, and h=5
Volume small cone V1= 1/3 *π*5²*5 = 5³/3 *π
2) large cone has r=5, and h=21-6=15, h=15
Volume large cone V2= 1/3 *π*5²*15 = 5³*π
3) whole volume
5³/3 *π + 5³*π=5³π(1/3+1)=((5³*4)/3)π=(500/3)π≈166.7π≈523.6
Area
we see 2 right triangles,
Area of the triangle=1/2*b*h, where b -base, h -height
1) small one, b=5, h=5
A1=(1/2)*5*5=25/2
2)large one, b=5, h=15
A2=(1/2)*5*15=75/2
3)
whole area=A1+A2=25/2+75/2=100/2=
50