<h3>
Answer: 5</h3>
Work Shown:
g = number of hours that Gary exercises
3g-2 = number of hours that Jessica exercises
(g) + (3g-2) = 18
4g-2 = 18
4g = 18+2
4g = 20
g = 20/4
g = 5
Gary exercises 5 hours per week.
Answer:
17. surface area ≈ 441.84
04π m² or 1387.38 m²
18. Ratio of volumes = 8/27
19. volume of the smaller solid = 339 yards³
Step-by-step explanation:
17 .
To find the surface area of the sphere we have to find the radius of the sphere first.
volume of a sphere = 4/3πr³
volume = 1548π m³
r = ?
volume of a sphere = 4/3πr³
1548π = 4/3 × π × r³
multiply both sides by 3/4
1548π × 3/4 = πr³
4644π/4 = πr³
1161π = πr³
divide both sides by π
r³ = 1161
cube root both sides
r = ∛1161
r = 10.5101942
r ≈ 10. 51
surface area of a sphere = 4πr²
surface area = 4 × π × 10.51²
surface area = 4 × 110.4601 × π
surface area = 441.8404π m²
surface area = 441.8404 × 3.14 = 1387.378856 m² ≈ 1387.38 m²
18
If two figure or solid are similar with scale factor or ratio of x/y then the ratio of their volume is (x/y)³. If the ratio of of two similar prism is 2 : 3 the volume will be (2/3)³ = 8/27 .
19
If two solids are similar then the ratio of their surface area is the squared of the scale factor.
121/361 = (x/y)²
square root both sides
x/y = 11/19
If two solids are similar then the ratio of their volume is the cube of the scale factor.
(11/19)³ = a/1747
1331/6859 = a/1747
cross multiply
6859a = 2325257
divide both sides by 6859
a = 2325257/6859
a = 339.008164455
a ≈ 339 yards³
volume of the smaller solid ≈ 339 yards³
Answer:
The answer is B. (-7,-2)
Step-by-step explanation:
Multiply the first equation by 7,and multiply the second equation by -6.
7(−3x+6y=9)
−6(5x+7y=−49)
Becomes:
−21x+42y=63
−30x−42y=294
Add these equations to eliminate y:
−51x=357
Then solve−51x=357for x:
−51x=357 Divide both sides by -51
x=-7
Write down an original equation:
−3x+6y=9
Substitute−7forxin−3x+6y=9:
(−3)(−7)+6y=9
6y+21=9(Simplify both sides of the equation)
6y+21+−21=9+−21(Add -21 to both sides)
6y=−12
y=-2
