Question 1149259
.
<pre>

Let x = the number of gallons consumed by the 1-st car and y = that for the 2-nd car.


Then you have this system of 2 equations in 2 unknowns


      x +   y =   65       (1)    (65 gallons of gas, total)

    40x + 15y = 1600       (2)    (miles, total)


There are many methods to solve the system.
For example, you may use the Elimination method.
For it, multiply eq(1) by 40 (both sides).  Keep eq(2) as is


    40x + 40y = 65*40      (1')   

    40x + 15y = 1600       (2')    


Next, subtract eq(2') from eq(1).  You will get


          40y - 15y = 65*40 - 1600 

          25y        = 1000

            y        = 1000/25 = 40.


<U>ANSWER</U>.  2-nd car consumed 40 gallons of gas;  1-st car consumed  the rest  65-40 = 25 gallons.
</pre>

Solved.


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Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.

in this site.


The referred lessons are the part of this online textbook under the topic "<U>Systems of two linear equations in two unknowns</U>".



Save the link to this online textbook together with its description


Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson


to your archive and use it when it is needed.