Hello,
x²+2*3x+3²+7-9=0
==>(x+3)²-2=0
==>(x+3-√2)(x+3+√2)=0
==> x=-3+√2 or x=-3-√2
Answer:
28
Step-by-step explanation:
The answer is 28 because this triangle will add up to 180 degrees and 79 + 73 = 152 and
180 - 152 = 28 so 28 is our missing angle!
Hope this helps you!
Answer:
204/325
Step-by-step explanation:
You can work this a couple of ways. We expect you are probably expected to use trig identities.
cos(A) = √(1 -sin²(A)) = 24/25
sin(B) = √(1 -cos²(B)) = 12/13
cos(A -B) = cos(A)cos(B) +sin(A)sin(B) = (24/25)(5/13) +(7/25)(12/13)
= (24·5 +7·12)/325
cos(A -B) = 204/325
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The other way to work this is using inverse trig functions. It is necessary to carry the full calculator precision if you want an exact answer.
cos(A -B) = cos(arcsin(7/25) -arccos(5/13)) = cos(16.2602° -67.3801°)
= cos(-51.1199°) ≈ 0.62769230 . . . . (last 6 digits repeating)
The denominators of 25 and 13 suggest that the desired fraction will have a denominator of 25·13 = 325, so we can multiply this value by 325 to see what we get.
325·cos(A-B) = 204
so, the exact value is ...
cos(A -B) = 204/325
ANSWER
EXPLANATION
The first equation is
The second equation is
We want to eliminate y, so we multiply the first equation by
We now subtract equation (3) from (2)
Multiply both sides by
Substitute into the first equation to solve for x .
Multiply to obtain
Multiply both sides by 2.
The solution is
Answer:
∠ F = 80°
Step-by-step explanation:
The sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 6 , then
sum = 180° × 4 = 720°
Sum the interior angles and equate to 720
7x + 7x + 4x + 7x + 7x + 4x = 720
36x = 720 ( divide both sides by 36 )
x = 20
Then
∠ F = 4x = 4 × 20° = 80°