Simply it as follows:
1 + 39 = 40
2 + 38 = 40 etc
18 + 22 = 40
19 + 21 = 40
There are 19 of these plus 40 itself . . .therefore 20 of them
20 x 40 = 800
And finally the last number not used, 20
Therefore 800 + 20 = 820
<span>2x^2 +3x -4 + 8 - 3x -5x^2 +2
answer is
</span>-3x^2 +6
hope that helps
Answer:
It had flown 2620 ft along the diagonal.
Step-by-step explanation:
When the plane is taking off it forms we can form a triangle with it's height, horizontal distance and diagonal distance, which can be seen in the attached drawing. We can use the sine relation on the right triangle to determine "x", as shown below:
sin(11°) = 500/x
x*sin(11) = 500
x = 500/[sin(11)] = 2620 ft
It had flown 2620 ft along the diagonal.
The area of the circle in pi units when the diameter of this circle is 6 centimeters is 9π centimeters.
<h3>What is the area of the circle?</h3>
The area of the circle is the space occupied by it. It is the product of pi and square of its diameter divided by 4. The area of the circle can be given as,

Here (d) is the diameter of the circle. The diameter of the circle is 6 cm.

Put this value in the above formula to find the area of the circle as,

Thus, the area of the circle in pi units when the diameter of this circle is 6 centimeters is 9π centimeters.
Learn more about the area of the circle here;
brainly.com/question/402655
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