4x^2-25= (2x)^2-5^2=(2x-5)(2x+5)
Used: a^2-b^2=(a+b)(a-b)
(a) Truck carries 90 gallons of diesel fuel to 660 miles.
So, 1 gallon of diesel fuel to 660/90 = 22/3 miles.
30 gallons of diesel fuel to = 220 miles.
Hence, if x-axis represents the number of miles and y-axis represents the number of gallons, then, (660, 90) and (220, 30) are points on the graph.
Join (660, 90) and (220, 30), we get the graph of a line.
Note that (0, 0) is also a point on the line.
Equation of the line is .
(b) x represents the number of miles. Therefore, the possible values for x is the closed interval [0, 660].
Hence, the domain of the function is [0, 660].
(c) Origin represents that the truck is not moving and there is no diesel fuel loaded in the truck.
Answer:
51.1 ≈ r
Step-by-step explanation:
"A bicycle wheel travels 321 in for each revolution"- means that 321 is the circumference of the wheel that is a circle.
C = 2· π· r
What is the radius of the wheel ?
321 = 2· π· r, divide both sides of the equation by 2 π
(321/2·π) = r , use calculator, solve and round the answer
51.1 ≈ r
My answer would be 8.. I may not be correct, but I tried. So, I placed the numbers from least to greatest and split it 1’s and 2’s VS 3’s and 4’s. I just added 1 plus 2 plus 2 and a half plus 2 and a half and got 8. I also added (3+3+3)+3 and a half plus 3