First you subtract 3 from both sides. 3-3 and 7-3, that cancels out 3 which leaves you with r>4.
Answer:
For the given expression: 
Step-by-step explanation:
Here, the given expression in statement form is given as:
5 X minus Y equals 6 + negative 2 X plus Y = 8
Now, converting the given statement mathematically, we get:
5X - Y = 6 + (-2X) + Y = 8
Now, considering first and the last terms,we get:
5 X - Y = 8 .... (1)
and , considering second and the last terms,we get:
6 + (-2X) + Y = 8 or, -2X + Y = 2 ......... (2)
Adding (1) and (2) , we get:
5 X - Y - 2 X + Y = 8 + 2
or, 3 X = 10
or, X = 10/3 = 3.34
Now, 5X - Y = 8
or, 
Hence, for the given expression:

Answer:
No, because the ratio of pay to hours is not the same for each pair of value.
Speed of the ship in the second hour = (62.5 * x ) / 100 kph.
In third hour it is [(62 * x) / 100 ] * x/100]
is 4th hour its is the above * x/100 again so we can now form the equation
62.5x x x
------- * ---- * ---- = 32
100 100 100
62,5 x^3 = 32,000,000
x^3 = 512,000
x = 80 <----- Answer to (a)
(b) Ship travels 62.5 in first hour then this falls by a common ratio of 0.8 each hour so we have a geometric sequence
Dist travelled in 6 hours = a1 1 - r^n
-------- = 62.5* (1 - 0.8^6) / 1 -0.8 = 230.56
1 - r
Answer is 230.56 km
R/6=14
multiply each side by 6 and you get
r=14×6
r=84