Question 1051163
Let x be the number of large frames, 
y be the number of small frames, 
Since she bought 11 frames, then {{{x+y=11}}}
Woman spent ${{{10x}}} on all large frames and ${{{5y}}} on small frames
{{{10x+5y=70}}}
The system of equations is
{{{system(x+y=11, 10x+5y=70)}}}
Divide the second equation by 5
{{{system(y=11-x, 2x+y=14)}}}
Substitute {{{y=11-x}}} into the second equation
{{{2x+11-x=14}}}
{{{x=14-11}}}
{{{x=3}}}
Substitute {{{x=3}}} into the first equation
{{{y=11-3}}}
{{{y=8}}}
Womann bought 3 large and 8 small frames

Answer: 3 large and 8 small frames