Answer:
Second option: 81y^4 - 16x^2, the difference of squares
Step-by-step explanation:
(9y^2-4x)(9y^2+4x) is a special product named difference of squares, then we can apply this formula:
(a-b)(a+b)=a^2-b^2, with a=9y^2 and b=4x, then:
(9y^2-4x)(9y^2+4x)=(9y^2)^2 - (4x)^2
(9y^2-4x)(9y^2+4x)=(9)^2 (y^2)^2 - (4)^2 (x)^2
(9y^2-4x)(9y^2+4x)=81y^(2*2) - 16x^2
(9y^2-4x)(9y^2+4x)=81y^4 - 16x^2
Answer: y-intercept: (0,-6)
150 + 20x, where x is the number of cellphones sold
Answer: 113.04
Step-by-step explanation: The equation for the area of a circle is pi r squared so you have to find the radius first. To find the radius, find the diameter first. A way to do this which was easiest for me was dividing 37.68 by pi (3.14), which is 12. Divide the diameter by 2 to find the radius, 6.
Now use the equation from the beginning, pi r squared. So plug in pi as 3.14, then the radius as 6. It is important to always square the radius first, which would be 36. Now multiply 36 by 3.14, and there should be your answer.
Answer:
C = 100p + 200
Step-by-step explanation:
Because C is the total cost per day, 200 is the y-intercept because it's paid daily.
The 100 is the slope since "he pays a cost of $100 per phone produced)".
