Answer:
a) v = 12.21m/s
a = 4.07 m/s²
b)v = 11.24m/s
a = 3.75 m/s²
Step-by-step explanation:
a) Dividing the moviment into two parts:
I - With acceleration
v = v₀ + at
s = s₀ + v₀t + at²/2
- v₀ = 0
- s₀ = 0
- a = ?
- v = ?
- t = 3s
- s = x
v = v₀ + at
v = 3a ⇒ a = v/3
s = s₀ + v₀t + at²/2
x = v/3.3²/2
x = 3v/2
II - Uniform
s = s₀ + vt
s = 100
s₀ = x
v = v
t = 9.69 - 3 = 6.69s
s = s₀ + vt
100 = x + v*6.69
100 = x + 6.69v
As x = 3v/2
100 = 3v/2 + 6.69v
100 = 1.5v + 6.69v
100 = 8.19v
v = 12.21m/s
a = v/3 = 4.07 m/s²
b) Dividing the moviment into two parts:
I - With acceleration
v = v₀ + at
s = s₀ + v₀t + at²/2
- v₀ = 0
- s₀ = 0
- a = ?
- v = ?
- t = 3s
- s = x
v = v₀ + at
v = 3a ⇒ a = v/3
s = s₀ + v₀t + at²/2
x = v/3.3²/2
x = 3v/2
II - Uniform
s = s₀ + vt
s = 200
s₀ = x
v = v
t = 19.30 - 3 = 16.30s
s = s₀ + vt
200 = x + v*16.3
100 = x + 16.3v
As x = 3v/2
200 = 3v/2 + 16.3v
200 = 1.5v + 16.3v
200 = 17.8v
v = 11.24m/s
a = v/3 = 3.75 m/s²
It is incorrect because when you times a negative by a positive. It is a negative number.
Solve for y for both equations then equate and solve:
5x + 9y = 160
9y = 160 - 5x
y = 160/9 - 5/9x
9x + 8y = 202
8y = 202 - 9x
y = 202/8 - 9/8x
160/9 - 5/9x = 202/8 - 9/8x (common denominator is 72)
1280/72 - 40/72x = 1818/72 - 81/72x
1818/72 - 1280/72 = 81/72x - 40/72x
538/72 = 41/72x
538 = 41x
538/41 = x
x = 13 5/41
Answer:
12x - 6
Step-by-step explanation:
8x - 3 + 4x - 3
12x - 6
x = - 2
