Answer:
Two solutions (-4,-7) and (4,7)
Step-by-step explanation:
x = y + 3
x*y = 28
(y+3)*y=28
y^2+3y-28=0
(y+7)(y-4)=0
y=-7, y=4
x=-4, x=7
Answer:
h = 4cm
Step-by-step explanation:
Diameter = 18cm
Radius = Diameter/2 = 18/2 = 9cm
V = 1/3*pi*r^2*h
We know that the volume is 108pi cm^3. We can just plug in 108pi cm^3 for V and we also know that our Radius (r) is 2.
So,
108 pi = 1/3*pi*9^2*h
108 pi = (81pi*h)/3
multiply 3 from both side
108pi*3 = (81pi*h)/3 *3
324pi = 81pi*h
Now divide the 81pi from both side
324pi/81pi = (81pi*h)/81pi
4 = h
So the height is 4cm
Answer:
900π m2
Step-by-step explanation:
surface are of a sphere is 4π(r)^2
now diameter is 30m,so radius will be 15 m
how, 4π(15)^2=900π (m2)
I think the answer is 78.