High School

Javier has saved [tex]$55[/tex] toward the purchase of an iPod. The iPod costs [tex]$145[/tex]. Which equation represents the amount Javier needs to save to buy the iPod?

A. [tex]55 - x = 145[/tex]
B. [tex]55 + x = 145[/tex]
C. [tex]145 \times 55 = x[/tex]
D. [tex]145x = 55[/tex]

Answer :

Javier has already saved \[tex]$55, and the iPod costs \$[/tex]145. If we let [tex]$x$[/tex] represent the additional amount he needs to save, then together the amount he has plus the amount he still needs equals the total cost. That is, we have:

[tex]$$55 + x = 145.$$[/tex]

To solve for [tex]$x$[/tex], subtract 55 from both sides:

[tex]$$x = 145 - 55.$$[/tex]

This shows that Javier must save an additional \[tex]$90. The equation representing this situation is

$[/tex][tex]$55 + x = 145,$[/tex]$

which corresponds to option B.