There was $135 in Roland's bank account after the two-month period.
Step-by-step explanation:
Step 1:
Roland out $180 in his account at the beginning of July. This reduced by 25% over the next two months.
We need to determine how much 25% of $180 is. To do so we convert 25% into a fraction and multiply with 180.
25% of $180 
So an amount of $45 reduced over two months.
Step 2:
To calculate the money Roland has in his account after two months, we subtract the amount reduced from the amount of money in his account at the beginning of July.
The amount of money in his bank account after the two-month period 
So there was $135 in Roland's bank account after the two-month period.
Answer:
The least common denominator would be 42.
Step-by-step explanation:
6 and 7 don't share any common multiples with any other number besides 6 or 7.
6 * 7 = 42
Answer:
Option B - graphing is the correct answer.
Step-by-step explanation:
To solve a system of inequalities we need graphing. Inequality tells us about the relative size of two values. When we graph the x and y co-ordinates, the solution is not the drawn line, but the area of the coordinate plane that satisfies the inequality. In inequalities, multiple solutions can be possible.
Plug and chug method does not a complete solution, it only tells where a point belongs. Guess and check does not apply here.