Two families go to the cinema.
the smith family buy tickets for one adult and four children
and pay £19
the jones family buy tickets for two adults and two children
and pay £17
what is the cost of one child’s ticket?

Step-by-step explanation:

x= cost of 1 adult ticket

y=cost of 1 kid ticket

so 1 adult+4 childeren=x+4y=19

2 adults and 2 childern=2x+2y=17

elimination

x+4y=19

2x+2y=17

multiply firest equation by -2

-2x-8y=-38

add to first equatuion

-2x-8y=-38

2x+2y=17 +

0x-6y=21

-6y=-21

multiply -2

6y=21

divide by 6

y=21/6=7/2

subsitute

2x+2y=17

2x+2(7/2)=17

2x+14/2=17

2x+7=17

subtract 7 from both sides

2x=10

divide by 2

x=5

1 adult ticket costs £5

1 kid ticket costs £7/2 or £3 and 1/2 or £3.5

hope this helps and give me brainliest pls

Step-by-step explanation:

f(4) = 42 + 5 =21, f(-10) = (-10)2 +5 = 105 or alternatively f: x → x2 + 5.

The phrase "y is a function of x" means that the value of y depends upon the value of x, so:

y can be written in terms of x (e.g. y = 3x ).

If f(x) = 3x, and y is a function of x (i.e. y = f(x) ), then the value of y when x is 4 is f(4), which is found by replacing x"s by 4"s .

If f(x) = 3x + 4, find f(5) and f(x + 1).

f(5) = 3(5) + 4 = 19

f(x + 1) = 3(x + 1) + 4 = 3x + 7