The correct answer is: [B]: " (2, 5) ".
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Given:
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-5x + y = -5 ;
-4x + 2y = 2 .
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Consider the first equation:
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-5x + y = -5 ; ↔ y + (-5x) = -5 ;
↔ y - 5x = -5 ; Add "5x" to each side of the equation; to isolate "y" on one side of the equation; and to solve in terms of "y".
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y - 5x + 5x = -5 + 5x
y = -5 + 5x ; ↔ y = 5x - 5 ;
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Now, take our second equation:
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-4x + 2y = 2 ; and plug in "(5x - 5)" for "y" ; and solve for "x" :
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-4x + 2(5x - 5) = 2 ;
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Note, 2(5x - 5) = 2(5x) - 2(5) = 10x - 10 ;
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So: -4x + 10x - 10 = 2 ;
On the left-hand side of the equation, combine the "like terms" ;
-4x +10x = 6x ; and rewrite:
6x - 10 = 2 ;
Now, add "10" to each side of the equation:
6x - 10 + 10 = 2 + 10 ;
to get:
6x = 12 ; Now, divide EACH side of the equation by "6" ; to isolate "x" on one side of the equation; and to solve for "x" ;
6x/6 = 12 / 6 ;
x = 2 ;
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Now, take our first given equation; and plug our solved value for "x" ; which is "2" ; and solve for "y" ;
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-5x + y = -5 ;
-5(2) + y = -5 ;
-10 + y = -5 ; ↔
y - 10 = -5 ;
Add "10" to each side of the equation; to isolate "y" on one side of the equation; and to solve for "y" ;
y - 10 + 10 = -5 + 10 ;
y = 5 .
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So, we have, x = 2 ; and y = 5 .
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Now, let us check our work by plugging in "2" for "x" and "5" for "y" in BOTH the original first and second equations:
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first equation:
-5x + y = -5 ;
-5(2) + 5 =? -5?
-10 + 5 =? -5 ? YES!
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second equation:
-4x + 2y = 2 ;
-4(2) + 2(5) =? 2 ?
-8 + 10 =? 2 ? Yes!
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So, the answer is:
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x = 2 , y = 5 ; or, "(2, 5)" ; which is: "Answer choice: [B] " .
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Answer:
<em>The height of the bullding is 717 ft</em>
Step-by-step explanation:
<u>Right Triangles</u>
The trigonometric ratios (sine, cosine, tangent, etc.) are defined as relations between the triangle's side lengths.
The tangent ratio for an internal angle A is:
The image below shows the situation where Ms. M wanted to estimate the height of the Republic Plaza building in downtown Denver.
The angle A is given by his phone's app as A= 82° and the distance from her location and the building is 100 ft. The angle formed by the building and the ground is 90°, thus the tangent ratio must be satisfied. The distance h is the opposite leg to angle A and 100 ft is the adjacent leg, thus:
Solving for h:
Computing:
h = 711.5 ft
We must add the height of Ms, M's eyes. The height of the building is
711.5 ft + 5 ft = 716.5 ft
The height of the building is 717 ft
Answer:
it would be E
Step-by-step explanation:
20x60= 4800
480x10= 1200
4800+1200= 6000
Answer:
B
Step-by-step explanation:
x²+2x=19 add 1 to both sides which gives you x²+2x+1=20
x²+2x+1 is the same as (x+1)²
Therefore (x+1)²=20
Answer:
1 to 3
Step-by-step explanation:
3 blue: 9 yellow
Divide each side by 3
3/3 : 9/3
1 blue: 3 yellow
1 to 3
