Answer:
Time machine one = 3.56
Time machine two = 4.56
Step-by-step explanation:
Let machine 2 do the job in x hours
Let machine 1 do the job in x - 1 hours.
The general formula for this problem is
Time = A*B/(A + B)
Givens
Time = 2 hours
B = x hours alone
A = x - 1 hours alone.
#################
x *( x - 1)
======= = 2
(x + x - 1)
(x^2 - x)/(2x - 1) = 2
x^2 - x = 2(2x - 1)
x^2 - x = 4x - 2
x^2 - 5x + 2 = 0
a = 1
b = - 5
c = 2
This gives 2 roots
x = 4.56
x = 0.43
The second root will not work because when 1 is subtracted from 0.43 the time give will be minus, which won't work.
Time for machine 2 is 4.56
The time for machine 1 is 3.56
Check
(A * B)/(A + B) = 2
A = 4.56
B = 3.56
Time = 4.56*3.56/(4.56 + 3.56)
Time = 16.2336/(8.12)
Time = 1.9992
The rounding error in the check comes from the rounding error in the times.
Answer:
3x+2x=total number
Step-by-step explanation:
Each of those bones pictures are equal to 2 bones. The question is asking, how many more rib bones than skull and jaw bones combined, so you’re gonna have to do some addition and subtraction.
You take the number of skull bones, which is 1(2), and add that to the number of jaw bones, which is 0. Giving you a total of 2 bones.
Then you are taking the rib bones 3(2) and finding out that you have 6.
So with that information, you can find out that there are 4 more rib more than skull and jaw bones combines (6-2=4)
Answer:
(-2, 4)
Step-by-step explanation:
~When reflecting a point of the x-axis, the x value (or first number inside the parenthesis) does not change.
The reason the x-value does not change is because you are reflecting over the x-axis, making the point go up or down. That will change the y-value but the x-value only changes if you move to the left or the right. In this case, you can see that the point's x-value is -2, so that will not change. It's current y-value however is -4. When reflecting over an axis, the number that is changing (in this case the y-value) will just be flipped from positive to negative, or vise versa. In this case, -4 will be reflected to be 4, making point C reflected over the x-axis (-2, 4).
Answer:
4
Step-by-step explanation:
ΔABC is congruent with ΔDEF. That means the corresponding sides are congruent.
Look at the order of the letters. EF are the last two letters of ΔDEF. So this corresponds with the last two letters of ΔABC. Therefore, EF ≅ BC.
EF ≅ BC
x² + 8x = 48
x² + 8x − 48 = 0
(x + 12) (x − 4) = 0
x = -12 or 4
Since x can't be negative, x = 4.
