Question 889811
1.{{{A+B=51}}}
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{{{5*B-7=1+8*A}}}
2.{{{-8A+5B=8}}}
Multiply eq. 1 by 8 and add to eq. 2,
{{{8A+8B-8A+5B=408+8}}}
{{{13B=416}}}
{{{highlight(B=32)}}}
From eq. 1,
{{{A+32=51}}}
{{{highlight(A=19)}}}