I NEED HELP QUICKLY!!! What is the sum of the first 140 positive multiples of 3?
1 answer:
Answer:
C
Step-by-step explanation:
The multiples of 3 are
3, 6, 9, 12, 15, ...........
The terms form an arithmetic sequence with common difference of 3.
The sum to n terms is
=
[2a₁ + (n - 1)d ]
where a₁ is the first term and d the common difference
Here a₁ = 3 and d = 3, thus
=
[ (2 × 3) + (139 × 3) ]
= 70(6 + 417) ] = 70 × 423 = 29610 → C
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Answer:
Step-by-step explanation:
<u>Equation of a circle</u>
where:
- (a, b) is the center
- r is the radius
From inspection of the diagram, the center of the circle <em>appears</em> to be at point (-3, 2), although this is not very clear. Therefore, a = -3 and b = 2.
Substitute these values into the general form of the equation of a circle:
Again, from inspection of the diagram, the <u>maximum vertical point</u> of the circle appears to be at y = 5. Therefore, to calculate the radius, subtract the y-value of the center point from the y-value of the maximum vertical point:
⇒ radius (r) = 5 - 2 = 3
Substitute the found value of r into the equation:
Therefore, the final equation of the given circle is:
