C=1500+4x where x is cds, C is cost
R=10x where R is revenue
then, P=R-C
P=10x-1500-4x
P=6x-1500
set P=0
1500=6x
x=250
check, C=1500+4*250, R=10*250
C=250, R=250
They need to sell 250 cds before they make profit
Answer:
Unit rate by which the runner completed the marathon is 0.13 miles per minute.
Step-by-step explanation:
A runner competed a marathon of 26.2 miles in 210 minutes.
we can get unit rate by unitary method.
∵ In 210 minutes a runner completes the distance = 26.2 miles
∴ In 1 minute runner will complete the distance = 
= 0.125 miles per minute
≈ 0.13 miles per minute
Therefore, unit rate by which the runner completed the marathon is 0.13 miles per minute.
-10 because its a negative and that's the opposite of the greatest itreger
<h2>Steps:</h2>
So for this, we will be completing the square to solve for m. Firstly, subtract 8 on both sides:

Next, divide both sides by 2:

Next, we want to make the left side of the equation a perfect square. To find the constant of this perfect square, divide the m coefficient by 2, then square the quotient. In this case:
-8 ÷ 2 = -4, (-4)² = 16
Add 16 to both sides of the equation:

Next, factor the left side:

Next, square root both sides of the equation:

Next, add 4 to both sides of the equation:

Now, while this is your answer, you can further simplify the radical using the product rule of radicals:
- Product rule of radicals: √ab = √a × √b
√12 = √4 × √3 = 2√3.

<h2>Answer:</h2>
In exact form, your answer is 
In approximate form, your answers are (rounded to the hundreths) 
Answer:
Total pencils: 17
Total rulers: 15
Step-by-step explanation:
"I will buy 15 pencils."
15 * 8p = £1.20
15 pencils
"Then I will buy as many rulers as possible."
£5 - £1.20 = £3.80
£3.80/30p = 12 remainder 20p
12 rulers
"With my change, I will buy more pencils.”
20p/8p = 2 remainder 4 p
2 pencils
Total pencils: 17
Total rulers: 15