Answer: y = 1.8
Step-by-step explanation:
xy = 12.6 If x is 7 but 7 in the equation for x
7y = 12.6 Divide both sides by 7
y = 1.8
5x - 5 = x + 11
5x = x + 16
4x = 16
x = 4
Hi there ! i think is number one. or a
Formula of the Volume of a hemisphere:
V =


r³
144

=


r³
Multiply by 3 to cancel fraction in the right side
144

× 3 = 2

r³
432

= 2

r³
Divide by 2

on either sides to isolate r³

=

r³
2

and

cancel out
216 = r³
Take cube root to find the radius
![\sqrt[3]{216}](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7B216%7D%20)
=
![\sqrt[3]{r^3}](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7Br%5E3%7D%20)
6 = r
Radius is 6 unitsThe formula of the surface area of a hemisphere is:
S.A = 2

r² +

r²
=

(6)² +

(6)²
=2

× 36 + 36

= 72

+ 36

= 108

units² (in terms of

)
≈ 339.12 units²
Surface area = 108
units