Answer:
2
1
3
+
2
8
2
−
4
9
−
1
2
2
−
1
6
+
2
8
Step-by-step explanation:
Answer: 2x^2-7x-15
Step-by-step explanation:
reorder the terms (x*2+3)*(x-5)
multiply the parentheses
(2x+3)*(x-5)
collect like terms (2x^2-10x+3x-15)
product= 2x^2-7x-15
Answer:
Let the speed of the train be x km/h.
Case 1:
Distance = 288 km
Speed = x km/h
Time = Distance/Speed
= 288/x h
Case 2:
Distance = 288 km
Speed = (x+4) km/h
Time = 288/x + 4 h
Since 288/x > 288/x + 4
288/x - 288/x+4 = 1
288[1/x - 1/x+4 ] = 1
[ x + 4 - x / x(x + 4) ] = 1/288
[4 / x^2 + 4x ] = 1/288
x^2 + 4x = 1152
x^2 + 4x - 1152 = 0
x^2 + 36x - 32x - 1152 = 0
x(x + 36) - 32(x + 36) = 0
(x + 36)(x - 32) = 0
x + 36 = 0 , x - 32 = 0
x = -36 , x = 32
x = -36 , rejected since speed cannot be negative.
Therefore , speed of the train = 32 km/h
Step-by-step explanation:
y = ¼x + 2
m1 = ¼
m of line perpendicular = m2
the formula is : m1×m2 = -1
=> m2 = -1 ÷ m1
= -1 ÷ ¼ = -4
so, the equation is :
y = -4x - 7 (option A)
