Step-by-step explanation:
There are 13 numbers here:
30, 30, 31, 32, 42, 49, 58, 58, 67, 67, 69, 78, 90.
The median number is the 7th number, which is 58.
True
<span>Cos(A+B)=CosACosB-SinASinB
therefore Cos(A+A)= CosACosA - SinASinA
= Cos^2A - Sin^2A</span>
B is the right answer to this question
3x + y = 3
7x + 2y = 1
First isolate one of the variables (x or y) in one of the equations.
Isolate "y" in the first equation(because it is the easiest to isolate) and substitute it into the second equation.
3x + y = 3 Subtract 3x on both sides
3x - 3x + y = 3 - 3x
y = 3 - 3x
7x + 2y = 1
7x + 2(3 - 3x) = 1 [since y = 3 - 3x, you can substitute (3-3x) for "y"]
Multiply/distribute 2 into (3 - 3x)
7x + (3(2) - 3x(2)) = 1
7x + 6 - 6x = 1
x + 6 = 1 Subtract 6 on both sides
x = -5
Now that you know "x", substitute it into one of the equations (I will do both)
3x + y = 3
3(-5) + y = 3 [since x = -5, you can plug in -5 for "x"]
-15 + y = 3 Add 15 on both sides
y = 18
7x + 2y = 1
7(-5) + 2y = 1
-35 + 2y = 1 Add 35 on both sides
2y = 36 Divide 2 on both sides
y = 18
x = -5, y = 18 or (-5, 18)
For this case we have the following equation:
an = a1 + (n - 1) • d
Where,
a1 = 57
d = 66-57 = 9
For the term number 250 we have:
n = 250
Substituting the values:
a250 = 57 + (250 - 1) * 9
a250 = 2298
Answer:
D.2298
