Add all sides.
5x+2+3x+8+4x-1
Combine like terms
12x+9
Subtract nine to get it on the other side of the equal sign
12x= -9
Divide by twelve
x=-9/12
Simplify
x=-3/4
Plug in x.
Answer:
a. x = total - $5
b. x = $6
c. x = $10
Step-by-step explanation:
a. pen + book = total
Let x = book
$5 + x = total
x = total - $5
b. pen + book = total
Total = 411
$5 + x = $11
x = $11 - $5
x = $6
c. pen + book = total
Total = $15
$5 + x = $15
x = $15 - $5
x = $10