All you have to do is combine like terms. 2c and (-c) are like terms (-5b) and (-b) are like terms and a is a term. So, 2c combined with (-c) is C. (-5b) and (-b) combined is (-6b). Since a doesnt need to be combined with anything, you leave it as it is so your answer will then be c - 6b + a (this is the answer assuming that there is a + in front of the a. If there is a - sign, then just change your +a to -a at the end
The answer is letter d) 3
STEP 1:
determine equations needed
x= # of $10 tickets
y= # of $14 tickets
QUANTITY EQUATION
x + y= 800
COST EQUATION
$10x + $14y= $9,040
STEP 2:
multiply quantity equation by -14
-14(x + y)= -14(800)
-14x - 14y= -11,200
STEP 3:
add new quantity equation in step 2 to cost equation of step 1 to solve for x using elimination
-14x - 14y= -11,200
10x + 14y= 9040
y term cancels out
-4x= -2160
divide both sides by -4
x= 540 ten dollar tickets
STEP 4:
substitute x value in step 3 into either original equation
x + y= 800
540 + y= 800
subtract 540 from both sides
y= 260 fourteen dollar tickets
ANSWER: There were 540 $10 tickets and 260 $14 tickets sold.
Hope this helps! :)