Answer:
1, -3
Step-by-step explanation:
X + k y = 1
k x + y = 1 / * ( - k )
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x + k y = 1
- k² x - k y = - k
--------------------
x - k² x = 1 - k
x ( 1 - k² ) = 1 - k
x = ( 1 - k ) / ( 1 - k² ) = ( 1 - k ) / ( 1 - k ) ( 1 + k )
y = 1 - k( 1 - k )/( 1 - k² )
y = ( 1 - k ) / ( 1 - k² ) = ( 1 - k ) / ( 1 - k ) ( 1 + k )
a ) For k = - 1 this system has no solution.
b ) For k ≠ - 1 and k ≠ 1, the system has unique solution:
( x , y ) = ( 1/ (1 + k) , 1/( 1 + k ) ).
c ) For k = 1, there are infinitely many solutions.
Total distance John drove=450 miles
total time=8 hours
let the number of hours he drove on highway be x, number of hours he drove on turnpike will be (8-x) hours
since
distance=speed*time
distance traveled in highway=50x
distance traveled in turnpike=60(8-x)
thus the total distance will be:
50x+60(8-x)=450
simplifying the above
50x+480-60x=450
-10x=450-480
-10x=-30
thus
x=3 hours
Thus he drove on highway for 3 hours.
Answer:
Vvvgfffff
Step-by-step explanation:
I think the answer is 26.5 mpg. I divided 212 by 8 and got 26.5 as my answer.