Question 28246
0.5x-2y=17
2x+y=7

Let's multiply the second equation by 2;

0.5x-2y=17
4x+2y=14

Now, let's add the two equations side by side.

4.5x = 31 (If we divide both sides by 4.5)
x = 31/4.5 

Let's simplify 31/4.5;
31/4.5 = 310/45 = 62/9

So, x = 62/9

Now let's insert x's value into the second equation(you may insert it into the first equation as well);
2.62/9 + y = 7
124/9 + y = 7
 y = 7 - 124/9
y = -61/9