for 11, set them equal to each other, since they both equal y.
y=2x+5; y=3x-1
2x+5=3x-1
x=6
and then substitute that x-value to find y.
y=3(6)-1
y=18-1
y=17
for 14 you can substitute the bottom y-value (x+7) into the top equation.
2x=y-10; x+7=y
2x=(x+7)-10
x=-3
and then substitute that x-value to find y.
-3+7=y
y=4