x + 2y = 9
x + 3y = 13
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Solve for x in the first equation. Subtract 2y from both sides.
x = 9 - 2y
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Plug x into the second equation.
(9 - 2y) + 3y = 13
Combine like terms.
9 + y = 13
Subtract 9 from both sides.
y = 4
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Plug y back into the first equation.
x + 2(4) = 9
x + 8 = 9
Subtract 8 from both sides.
x = 1
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x = 1
y = 4
(x+1)(x-4)-(x-2) = 0
x²-4x+x-4-x+2 = 0
x²-4x-2 = 0
/\ = (-4)² - 4*1*(-2)
/\ = 16 + 8
/\ = 24
x = (-(-4)+/- \/24) / 2
x = (4+/-\/4*6)/2
x = (4+/-2\/6)/2
x = 2+/-\/6
x' = 2+\/6
x" = 2-\/6
Answer:
w = 
Step-by-step explanation:
The question is 
We can first use distributive property to simplify, the distributive property is 
Thus we have:
<em>Now we combine like terms and simplify to get the final answer for w</em><em>.</em>
Thus, w =
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
