Alright, so we'd use the combinations with repetition formula, so we choose from 4 schools to distribute to and distribute 8 blackboards. It's then
( 8+4-1)!/8!(4-1)!=11!/(3!*8!)=165
For at least one blackboard, we first distribute 1 to each school and then have 4 blackboards left, getting (4+4-1)!/4!(4-1)!=7!/(4!*3!)=35
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Standard Form is Ax + By = C
y=2x+5
-2x+y= -2x+2x +5
-2x + y = 5
Answer -2x + y = 5
Answer:
135°
Step-by-step explanation:
∠AOB = ∠COB = 90°
∠BOK = 45°
90 + 45 = 135°
