2 - 12 + 18
= -10 + 18
= 8
The answer is D.
Answer:
The area of the triangle is 
Step-by-step explanation:
Given:
Coordinates D (0, 0), E (1, 1)
Angle ∠DEF = 60°
△DEF is a Right triangle
To Find:
The area of the triangle
Solution:
The area of the triangle is = 
Here the base is Distance between D and E
calculation the distance using the distance formula, we get
DE = 
DE =
DE = 
DE = 
Base = 
Height is DF
DF =
DF = 
DF = 
Now, the area of the triangle is
= 
=
=
=
? I’m confused is there supposed to be a picture to this? I don’t see a expression so..
Answer:
Step-by-step explanation:
Find the sum of the first 42 terms of the following series, to the nearest integer.
2,7,12
Solution
The sum is given by
SUM_n=n/2*(a_1+a_n)
a_n=a_1+(n-1)d
a_1=2, n=42, d=5
The 42nd term is therefore given by
a_42=2+(42-1)5=207
SUM_42=42/2*(2+207)=21*209=4389
The sum of the first 42 terms of the series, therefore, is 4389
One is false, two is true. Hope I helped