Question

Together Sofia and jack saved $520. Sofia saved $100 more than jack how much did Sofia save?

Answer 1

Hello!

Let's use a system of equations.

s+j=520
s=100+j

Now we will plug in our x value to solve for j.

100+j+j=520
100+2j=520
2j=420
j=210

Now we plug our j value into the first equation.

s=210+100
s=310

Sofia saved $310, and Jack saved $210.

I hope this helps!

Answer 2

Hi!

Let's write some equations to solve this. 

s = Sofia
j = Jack

s + j = $520
j + $100 = s

Put the value of s into the first equation. 

j + $100 + j = $520
Simplify
j + j + $100 = $520
2j + $100 = $520
Subtract $100 from both sides
2j + $100 - $100 = $520 - $100
2j = $420
Divide both sides by 2
2j/2 = $420/2
j = $210

Now that we know Jack has $210, let's find out how much Sofia has by putting that value into one of the equations. 
$210 + $100 = s
Solve
$310 = s

Let's check our answer by putting the values into the first equation. 
$310 + $210 = $520
This equation is true, so our answer is correct!!

The answer is Sofia saved $310

Hope this helps! :)
-Peredhel