4x + 5y = 71 and 5x + 3y = 66

1.	4x + 5y = 71 and 5x + 3y = 66
Answer» ★FIND: $\bold{The}$ $\bold{value}$ $\bold{of}$ $\bold{'x'}$ $\bold{and }$ $\bold{'y'.}$ ★GIVEN: ➾ $\bold{4x + 5y = 71..EQ1}$ ➾ $\bold{5x + 3y = 66..EQ2}$ ★SOLUTION: ➯ $\bold{EQ1=>5(4x + 5y = 71)}$ ➯ $\bold{20x+25y=355..EQ3}$ ➯ $\bold{EQ2=>4(5x+3y=66)}$ ➯ $\bold{20x+12y=264..EQ4}$ $\bold{SUBTRACTING}$ $\bold{EQ3}$ $\bold{AND}$ $\bold{EQ4}$ ☞ $\bold{20x+25y-20x-12y=355-264}$ ☞ $\bold{13y=91}$ ☞ $\bold{y=91/13}$ ☞ $\bold{y=7}$ $\bold{sub,}$ $\bold{y=7}$ $\bold{in}$ $\bold{EQ1}$ $\bold{OR}$ $\bold{EQ2}$ ➛ $\bold{EQ1=>4x+5(7)=71}$ ➛ $\bold{4x+35=71}$ ➛ $\bold{4x=71-35}$ ➛ $\bold{4x=36}$ ➛ $\bold{x=36/4}$ ➛ $\bold{x=9}$ $\bold{so,}$ $\bold{(x,y)}$ $\bold{=}$ $\bold{(9,7)}$ ★VERIFICATION: $\bold{sub, }$ $\bold{(x, y) =(9, 7)}$ $\bold{in}$ $\bold{EQ1}$ $\bold{OR}$ $\bold{EQ2}$ ➥ $\bold{EQ1=>4(9)+5(7)=71}$ ➥ $\bold{36+35=71}$ ➥ $\bold{71=71}$ ➥ $\bold{EQ2=>5(9)+3(7)=66}$ ➥ $\bold{45+21=66}$ ➥ $\bold{66=66}$ ⛬ $\bold{(x,y)}$ $\bold{=}$ $\bold{(9,7)}$

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