This you answer x=-1/5y+-4/5
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X^2 - 5x = 12
x^2 - 5x + 6.25 = 12 + 6.25
(x - 2.5)^2 = 18.25
x - 2.5 = (+-) sqrt 18.25
x = 2.5 (+ - ) 4.27
x = 2.5 + 4.27 = 6.77 <==
x = 2.5 - 4.27 = -1.77 <==
<u><em>Answer:</em></u>
∠7 = 95°
<u><em>Explanation:</em></u>
<u>1- getting the value of x:</u>
In the given figure, angle 1 and angle 4 are vertically opposite angles.
Therefore, they are equal in measurement
This means that:
3x + 10 = 4x - 15
4x - 3x = 10 + 15
x = 25
<u>2- getting the value of angle 4:</u>
We know that:
x = 25 and ∠4 is 4x-15
This means that:
∠4 = 4(25) - 15
∠4 = 85°
<u>3- getting the value of ∠6:</u>
From the given figure, we can see that ∠4 and ∠6 are supplement angles, this means that their summation is 180°.
We have calculated that ∠4 is 85°, therefore:
180 = ∠4 + ∠6
∠6 = 180 - ∠4
∠6 = 180 - 85
∠6 = 95°
<u>4- getting the value of angle 7:</u>
From the drawing, we can note that ∠6 and ∠7 are vertically opposite angles. This means that they are equal in measurements.
Therefore:
∠7 = ∠6 = 95°
Hope this helps :)
To find the average of an amount of numbers, we simply add them up and divide them by the amount of numbers we have. For example, if we have 1,2, and 3 as our numbers, we can see that we have three numbers. Next, we add them up to get 1+2+3=6. Lastly, we divide 6 by the amount of numbers we have (3) to get 6/3=2 as our average. Applying that here, we see that there are four numbers. Next, we add them up using a calculator to get 5,678.54+3,665.77+4,231.98+4,768.99 =18345.28 . Finally, we divide that number by the amount of numbers we have (using a calculator) to get 18345.28/4=4,586.32, making B your answer.
Feel free to ask further questions, and Happy Halloween!