Answer :

multiply the first equation by 2 so you get 10a-2b=34 then add the two equations to eliminate the b variable so you have 13a=39 so a=3. plug in 3 into the second equation to solve for b and you get -2 and then plug in 3 and -2 into the first equation to check if they are equal which they are. answer is 3,-2
[tex]5a-b=17 <=>-b=17-5a => \boxed{b=5a-15} \\\\3a+2b=5\\\\3a+2(5a-15)=5\\\\3a+10a-30=5\\\\13a=5+30\\\\13a=35\\\\ \boxed{a=\frac{35}{13}}\\\\b=5*\frac{35}{13}-15 \\\\ b=\frac{175}{13}-15^{13} \\\\ b=\frac{175-195}{13} \\\\ \boxed{b= -\frac{20}{13}}[/tex]