You can try them out and see which one works.
a: f(2) = f(1) +6 = 5+6 = 11 . . . . . . not this one
b: f(1) = f(2) -6 = -1-6 = -7 . . . . . . not this one (5 ≠ -7)
c: f(2) = f(1) - 6 = 5 - 6 = -1 . . . . . this gives the right f(2)
d: f(2 = -6(f(1) = -6(5) = -30 . . . . not this one
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The appropriate choice is ...
... f(n +1) = f(n) - 6
— — — — —
You can also recognize that the next term is 6 less than the current one, so f(n+1) = f(n) - 6, which corresponds to the 3rd selection.
You have to times it by 100 - however much you want to decrease it by so your multiplier would 0.38
<h3>Answer:</h3>
A) ∠A = ∠A' = 38° and ∠B = ∠B' = 42°
<h3>Explanation:</h3>
The sum of angles in ∆ABC is 180°, so ...
... (2x -2) + (2x +2) + (5x) = 180
... 9x = 180
... x = 20
and the angles of ∆ABC are ∠A = 38°, ∠B = 42°, ∠C = 100°.
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The sum of angles of ∆A'B'C' is 180°, so ...
... (58 -x) +(3x -18) +(120 -x) = 180
... x +160 = 180
... x = 20
and ∠A' = 38°, ∠B' = 42°, ∠C' = 100°.
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The values of angle measures of ∆ABC match those of ∆A'B'C', so we can conclude ...
... A) ∠A = ∠A' = 38° and ∠B = ∠B' = 42°
Yes, an angle less than 90 degrees is acute.
