Answer:
225
Step-by-step explanation:
Using the basic components of summation ∑
∑n = n(n + 1) and ∑1 = n
Thus
∑ (2n - 1) ← for n = 1 to 15
= ∑2n - ∑1
= 2∑n - ∑1
= 2 ( n(n + 1)) - n
= n(n + 1) - n ← Evaluate for n = 15 ( the upper value )
= 15 × 16 - 15
= 240 - 15
= 225
Answer:
Area of ΔDEF = 12 in²
Step-by-step explanation:
Since they are similar, we have to find the scale factor
Scale Factor =
Scale Factor = 4/2
Scale Factor = 2
<u><em>This means The area of ΔABC is 2 times the area of ΔDEF</em></u>
So,
ΔABC = 2(ΔDEF)
Where Area of ΔABC = 24 in²
24 = 2(ΔDEF)
Dividing both sides by 2
=> Area of ΔDEF = 12 in²