Answer:
7. 1520.53 cm²
8. 232.35 ft²
9. 706.86 m²
10. 4,156.32 mm²
11. 780.46 m²
12. 1,847.25 mi²
Step-by-step explanation:
Recall:
Surface area of sphere = 4πr²
Surface area of hemisphere = 2πr² + πr²
7. r = 11 cm
Plug in the value into the appropriate formula
Surface area of the sphere = 4*π*11² = 1520.53 cm² (nearest tenth)
8. r = ½(8.6) = 4.3 ft
Plug in the value into the appropriate formula
Surface area of the sphere = 4*π*4.3² = 232.35 ft² (nearest tenth)
9. r = ½(15) = 7.5 m
Surface area of the sphere = 4*π*7.5² = 706.86 m² (nearest tenth)
10. r = ½(42) = 21 mm
Plug in the value into the formula
Surface area of hemisphere = 2*π*21² + π*21² = 2,770.88 + 1,385.44
= 4,156.32 mm²
11. r = 9.1 m
Plug in the value into the formula
Surface area of hemisphere = 2*π*9.1² + π*9.1² = 520.31 + 260.15
= 780.46 m²
12. r = 14 mi
Plug in the value into the formula
Surface area of hemisphere = 2*π*14² + π*14² = 1,231.50 + 615.75
= 1,847.25 mi²
Answer:
2
Step-by-step explanation:
As per the interval, x = 1 and y = 5/2
<u>Substitute x into the expression:</u>
3 - 1 = 2
You look at the sign behind the second term. Here are some examples...
2x + 8 - 4x
You are going to subtract 2x - 4x because there is a negative sign behind the 4x.
8y + 1 + y
You are going to add 8y + y because there is a positive sign behind the y.
4 + 2x - 5 + 7x
You are going to subtract 4 - 5 because there is a negative sign behind the 5.
You are going to add 2x + 7x because there is a positive sign behind the 7x.