Standard Form : f (x) = a(x - h)2 + k
Where in this equation (H,K) is the vortex of the parabola
<u>and there are four other ways to solving these quadratic</u>
1. Factoring
2. Completing the square
3. Your quadratic formula ( f (x) = a(x - h)2 + k )
4. Graphing
Set of equations that can be used to calculate rate for each plumber:
2A+8B+8C = 1,400 --- (1)
4A+7B+10C = 1,660 --- (2)
3A+9B+9C = 1,660 --- (3)
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2*(1) - (2)
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4A+16B+16C = 2,800
4A+7B+10C = 1,660 -
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9B+6C = 1,140 --- (4)
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3(2) -4(3)
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12A+21B+30C = 4,980
12A+36B+36C = 6,600 -
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-15B-6C = -1,620 --- (5)
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(4) + (5)
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9B+6C = 1140
-15B-6C = -1620 +
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-6B = -480 => 6B = 480 => B = 480/6 = 80
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Using (4), 9(80)+6C = 1140
720+6C = 1140 => 6C = 1140-720 = 420 => C = 420/6 = 70
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Using (1), 2A+8(80)+8(70) = 1400
2A+640+560 =1400 => 2A = 1400-640-560 = 200 => A = 200/2 = 100
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The rates are:
A = $100
B = $80
C = $70
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On Thursday, number of calls: A = 4 hrs, B = 6 hrs, C = 3 hrs
Money earned = 4*100+6*80+3*70 = $1,090
Answer:
37 and -18
Step-by-step explanation:
Let one number be x and other y
1 x + 1 y = 19 .............1
1 x -1 y = 55 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by 1
1 x 1 y = 19
1 x + -1 y = 55
Add the two equations
2 x = 74
/ 2
x = 37
plug value of x in (1)
1 x + 1 y = 19
37 + 1 y = 19
1 y = 19 -37
1 y = -18
y = -18
37 and -18
To find that you would do (such that x is the unknown) 3x+5(x+2)=106
and if you do this you will find that x=12
so the two numbers you are looking for are 12 and 14
Z = (X-Mean)/SD
<span>z1 = (165 - 150)/15 = +1 </span>
<span>z2 = (135 - 150)/15 = - 1 </span>
<span>According to the Empirical Rule 68-95-99.7 </span>
<span>Mean +/- 1SD covers 68% of the values </span>
<span>100% - 68% = 32% </span>
<span>The remaining 32% is equally distributed below z = - 1 and z = +1 </span>
<span>32%/2 = 16%
</span>
<span>Therefore,
</span>
<span>a) Number of men weighing more than 165 pounds = 16% of 1000 = 160 </span>
<span>b) Number of men weighing less than 135 pounds = 16% of 1000 = 160</span>
