Marcello is an artist who makes oil paintings and charcoal sketches. He sells each oil painting for $500 and each charcoal sketch for $300. Marcello wants to create 56 works total. Write and solve a system of equations to determine how many pieces of artwork he must sell in order to make exactly $20,000

He needs to sell 25 pieces of artwork.

Step-by-step explanation:

$500 for an oil painting.

$300 for a charcoal sketch.

56 pieces of artwork total.

$20,000 goal.

500 + 300

= 800

$800 for 1 oil painting and 1 charcoal sketch.

20,000 ÷ 800

= 25

He needs to sell 25 pieces of artwork to make $20,000.

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)