Multiply both sides by 10.
2b=990
divide both sides by 2
b= 495
Answer: a=5 b=2
Step-by-step explanation:
They both satisfy the equation as 5+2=7 and 5-2=3
Hope this helps!
Answer:

Step-by-step explanation:
Given:
The given inequality is:

The given inequality has variable 'x' on both sides of the inequality.
In order to solve such inequalities, we bring the variables on the same side as the first step in solving for 'x'.
Therefore, we could either add
on both sides or add
both sides to bring the variable terms on same side.
If we add
both sides, we get:

So, among all the given options, third option matches the above inequality.
Therefore, the first step in solving the given inequality is 
240 sec + 45 sec= 285 sec