Answer:
x=9
Step-by-step explanation:
3.5x - 11 = 20.5
Add 11 to each side
3.5x - 11+11 = 20.5+11
3.5x = 31.5
Divide each side by 3.5x
3.5x/3.5 = 31.5/3.5
x =9
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
Operación: (+6)-(3). Piso Final: +3
Inicial: +8 Operación: (+8)+(+1) Piso final: +9
Inicial: +10 Operación: (+10)-(4) Piso final: +6
to find the hypotenuse (or the ramp in question 4) you can use the equation
with a and b being the 3 feet and 9 feet and c being the unknown (ramp).
So if you plug 3 and 9 into the equation, it looks like this.
then square them.
simplify.
take the square root of both sides.
is approx. 9.5 so the answer would be H.
