Answer:
46 terms
Step-by-step explanation:
a₁=b, a₂₁= bₙ, d₁=9, d₂=4
n=?
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a₂₁= a₁+20d₁= a₁+20*9= a₁+180
bₙ= b₁+(n-1)d₂= a₁+4(n-1)
a₁+4(n-1)=a₁+180
4(n-1)=180
n-1= 180/4
n-1= 45
n=46
Answer:
sry I just wanted the points I'm in middle school so I don't know this stuff either but can you give free brainlyest I'm soo close to my next rank I'd really appreciate it if you would
Step-by-step explanation:
Not entirely sure, but I believe something like this:
∠1 + ∠2 = 180° since they are a linear pair;
Since ∠1 = ∠2, we can say:
∠1 + ∠1 = 180°
2(∠1) = 180°
∠1 = 90°
And since:
∠1 = ∠2
∠2 = 90°
So the angle between t and s is 90°;
An angle of 90° means t and s are perpendicular (⊥)