For the each of them simply substitute for x in each equation to see if you get the corresponding y , it doesnt really get any more straightforward than this
Use the given information as (x, y) points.
You have
(1, 34)
(2, 50)
(3, 66)
(4, 82)
The difference between renting for 1 day and 2 days is 50 - 34 = 16.
The difference between renting for 2 days and 3 days is 66 - 50 = 16
The difference between renting for 3 days and 4 days is 82 - 66 = 16
For each day you rent you pay $16.
Now look at renting for 1 day.
The rental for 1 day is $16, but for 1 day you pay $34.
$34 - $16 = $18
There is an extra $18 in the rental for every day. The $18 is fixed.
That means, to rent a truck, you must pay a fixed amount of $18 plus $16 per day.
total cost = daily cost + fixed cost
total cost = 16d + 16
c = 16d + 18
<span><span>4a+6b=10
4a=10-6b
a=(10-6b)/4
a=(5-3b)/2
</span>
<span>2a-4b=12
2((5-3b)/2)-4b=12
(5-3b)-4b=12
5-7b=12
-7b=7
b=-1
</span>
<span>2a-4b=12
2a-4(-1)=12
2a+4=12
2a=8
a=4
a=4, b=-1 </span>
12a=48</span>
