X - the number
3x - 7 = -4 |add 7 to both sides
3x = 3 |divide both sides by 3
x = 1
Answer:
20 mph
Step-by-step explanation:
Let speed of Train a = Va mph
Let speed of Train b = Vb mph
Va = Vb + 30
Let time taken for Train a = Ta
Let time taken for Train b = Tb
time taken = distance travelled/speed
Ta = 350/Va = 350/(Vb+30)
Tb = 140/Vb
But they both travel in the same amount of time.
So, Ta = Tb

Cross multiply

Divide both sides by 210

Answer:
125 p^3 g^3
Step-by-step explanation:
(5pg)^3
We know that (ab)^c = a^c * b^c
5^3 p^3 g^3
125 p^3 g^3
Answer:
360
Step-by-step explanation:
Formula
Sides -2 ×180
4-2=2×180=360