Speak in English please. I would be more pleased to help if you write in English.
Answer:
(x - 3)(x + 7)
Step-by-step explanation:
x^2 + 4x - 21
=> x^2 + 7x - 3x - 21
=> x(x + 7) -3(x + 7)
=> (x + 7)(x - 3)
Answer:
the cyclists rode at 35 mph
Step-by-step explanation:
Assuming that the cyclists stopped, and accelerated instantaneously at the same speed than before but in opposite direction , then
distance= speed*time
since the cyclists and the train reaches the end of the tunnel at the same time and denoting L as the length of the tunnel :
time = distance covered by cyclists / speed of cyclists = distance covered by train / speed of the train
thus denoting v as the speed of the cyclists :
7/8*L / v = L / 40 mph
v = 7/8 * 40 mph = 35 mph
v= 35 mph
thus the cyclists rode at 35 mph
Answer:
x = 62
Step-by-step explanation:
If the triangle has two values that are the same like your 6s that means that they have the same angle, so you take the angle(56 degrees) and subtract 180 and 56 making 124. You take 124 and divide it by 2. Making x =62.
Narrowing it down it's either a or c because the other 2 choices open downward (negative a).
Graphing the 2 parabolas choice c is narrower.
c