Y = mx + b
8x - 4y - 9 = 0
first you move the nine to the other side of the equal sign (add nine to both sides)
8x - 4y = 9
then you need to also move your 8x over to the other side as well (remember we are trying to get y by itself!)
- 4y = -8x + 9
then we are going to divide -4 to both sides
and you get
y = 2x - 9/4
we can then identify the slope as 2
so B. 2 would be your answer
hope this helped
One club member is 9 years old, one is 11 years old, two are twelve years old and four are fourteen years old.
The answer is: 3.91 inches .
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Note: Volume of cylinder: V = (base area) * (height);
in which: V = volume = 384 in.³ ;
h = height = 8 in. ;
Base area = area of the base (that is; "circle") = π r² ;
in which; "r" = radius;
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Solve for "r" :
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V = π r² * (8 in.) ;
384 in.³ = (8 in.) * (π r²) ;
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Divide EACH SIDE of the equation by "8" ;
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(384 in.³) / 8 = [ (8 in.) * (π r²) in.] / 8 ;
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to get:
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48 in.³ = (π r²) in.² * in. ;
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↔ (π r²) in.² * in. = 48 in.³ ;
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Rewrite this equation; using "3.14" as an approximation for: π ;
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(3.14 * r²) in.² * in. = 48 in.³
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Divide EACH SIDE of the equation by:
"[(3.14)*(in.²)*(in.)]" ; to isolate "r² " on one side of the equation;
(since we want to solve for "r") ;
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→ [(3.14 * r²) in.² * in.] / [(3.14)*(in.²)*(in.)] = 48 in.³ / [(3.14)*(in.²)*(in.)] ;
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→ to get: r² = 48/3.14 ;
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→ r² = 15.2866242038216561 ;
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To solve for "r" (the radius; take the "positive square root" of EACH side of the equation:
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→ +√(r²) = +√(15.2866242038216561)
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→ r = 3.9098112747064475286 ; round to 3.91 inches .
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The chances of picking an even number(a number that’s not odd) would be 1 out of 3
Let x represent the gallons of water that is 10% salt.
Let y represent the gallons of water that is 25% salt.
Now, write the system of equations:
x + y = 10
.10x +.25y = 0.20 • 10
1) To make the system easier to solve, multiply all the terms in .10x +.25y = 0.20(10) by 100 to make them integers.
10x + 25y = 20 • 10
10x + 25y = 200
2) Solve for x.
x + y = 10
x = 10 - y
3) Substitute x with 10 - y in the other equation.
10(10 - y) + 25y = 200
100 - 10y + 25y = 200
Combine like terms.
100 + 15y = 200
Subtract 100 from both sides.
15y = 100
y = 20/3 or 6 2/3
4) Now that we have the numerical value of y, solve for the value of x by substituting once more.
a) x + y = 10
x + 20/3 = 10 or x + 6 2/3 = 10 (either equation is fine)
x = 10/3 or x = 3 1/3
The manager should combine 3 1/3 (3.33) gallons of 10% salt water and 6 2/3 (6.67) gallons of 25% salt water.
5) Always check the answers to make sure.
a) x + y = 10
3 1/3 + 6 2/3 = 10
9 3/3 = 10
10 = 10
b) .10x +.25y = 0.20 • 10
.10(3 1/3) +.25(6 2/3) = 0.20 • 10
1/3 + 5/3 = 2
6/3 = 2
2 = 2
