




Combining like terms, we have



Remark
The quick answer is C does not represent a function. It has two y values for x = 2. These two points are (2,1) and (2,3). That eliminates C. No x can have 2 y values and be called a function. A function can have many x vales for a single y and still be a function.
A has all different x values, so it could be classed as a function. There are no values where x has more than 1 y value.
B also has all different x values. It too is a function.
Answer
A and B are both functions. C is not.
D <<<<< Answer
Answer:
(x,y,z)=( -2, -1 ,5)
Step-by-step explanation:
9x+2y-27z=-155 (1)
-11x-y+37z=208 (2)
19x+6y-52z=-304 (3)
(1) *3 ;(2) *6 ;(3)*1, you have
27x+6y-81z=-465 (1)
-66x-6y+222z=1248 (2)
19z+6y-52z=-304 (3)
(1) +(2), you have
-39x+141z= 783 (4)
(4) /3, you have
-13x +47z=261 (4)
(2) +(3), you have
-47x+170z=944 (5)
From ( 4) and (5), you have equations
-13x +47z=261 (4)
-47x+170z=944 (5)
(4)*(-47); (5)*13, you have
611x-2209z=-12,267 (4)
-611x+2210z=12,272 (5)
(4)+(5), you have
z=5
Replace z=5 in (4), you have
611x- 2209*5=-12,267
611x- 11,045 =-12,267
611x=-1222
x= -2
Replace x=-2, z=5 in (1) , you have
9*(-2) +2y -27*5=-155
-18+2y-135=-155
-18+2y=-20
2y=-2
y=-1
Result (x,y,z)=( -2, -1 ,5)
Answer:
<u>Finally, the trip of Thomas will take an hour and fifty minutes more than the normal time it usually takes.</u>
Step-by-step explanation:
1. Let's check all the information provided to answer the question:
Time of Thomas flight delay = 1 5/6 hours
Time of normal flight = x hours
2. How long did the trip finally take?
For calculating how long the trip finally took, we need to do the following sum:
Time of normal flight + Time of delay
Like we don't know the time of the normal flight, we will define it as x, then:
x + 1 5/6 hours
x + 1 hour and 50 minutes ⇒ 5/6 of an hour = 5/6 * 60 minutes = 50 minutes
<u>Finally, the trip of Thomas will take an hour and fifty minutes more than the normal time it usually takes.</u>