The answer is x=20. Hope this helps.
<h2>Answer: 250 Hamburgers sold</h2><h2>Step-by-step explanation:</h2><h2><u><em>x = hamburgers
</em></u></h2><h2><u><em>y = cheeseburgers
</em></u></h2><h2><u><em>x+y=434
</em></u></h2><h2><u><em>66 fewer cheeseburgers than hamburgers
</em></u></h2><h2><u><em>
</em></u></h2><h2><u><em> </em></u></h2><h2><u><em>y = x - 66
</em></u></h2><h2><u><em>Substitute y into the first equation
</em></u></h2><h2><u><em>x + (x-66) = 434
</em></u></h2><h2><u><em>2x = 434 + 66
</em></u></h2><h2><u><em>2x = 500
</em></u></h2><h2><u><em>x = 250 hamburgers sold</em></u></h2>
Answer:

Step-by-step explanation:
Multiply the numerator and denominator by the conjugate.
Paul
=$30,000 + ($2800 * 10 years)
=$30,000 + $28,000
=$58,000 total made in 10 years
Sharla
=$36,000 + ($2000 * 10 years)
=$36,000 + $20,000
=$56,000 total made in 10 years
Difference
=$58,000 - $56,000
=$2,000 difference
ANSWER: Paul made $2,000 more.
Hope this helps! :)