Answer:
B: {(3,1), (7,9)}
Step-by-step explanation:
For equation 2x-y=5, we can isolate y, so it's easier to solve later:
y = 2x - 5
y = (x - 4)^2
Now, notice that both equations are equal to y, so we can set them equal to each other:
(x-4)^2 = 2x-5
x^2-8x+16 = 2x - 5
x^2-10x+21=0
Now, we can factorize by finding 2 numbers that multiply to 21 and add up to -10:
(x-3)(x-7)=0
x=3 or x=7
Since B is the only one with the x values of 3 and 7, the answer must be B.
But to further check our answer, we can plug x back to any of the equations above to check for y:
(3-4)^2 = 1
(7-4)^2 = 9
Therefore, we can confirm that the answer is B.
mike charges 100 dollars service charge plus 65 dollars per hour.
amy charges 40 dollars service charge plus 80 dollars per hour.
the cost to repair from mike is 100 + 65 * x.
the cost to repair from amy is 40 + 80 * x.
let x = 3 and you get:
the cost to repair from mike is 100 + 65 * 3 = 295 dollars.
the cost to repaid from amy is 40 + 80 * 3 = 280 dollars.
as long as the time to repair is 3 hours or less, the cost to repair will be cheaper from amy.
4.86 is the answer to you're question.
