Question

Lia brought 21 shirts and plants. Her total was $357. Pants cost $25 each, and shirts cost $14.50 each. How many of each item did she buy? Show your work

Will give points

Answer 1

x=5 and y=16

Explanation:

x = number of pants

y = number of shirts

Set up equations:

1. 25x + 14.5y = 357
2. x + y = 21

Set the equations up as a system:

25x+14.5y=357

x+y=21

Steps:

Solve the system by substitution.

(You can also solve this system by elimination.)

25x + 14.5y= 357

x + y = 21

Step 1: Solve x+y=21 for x:

(x + y) − y = (21) − y(Subtract y from both sides)

x = −y + 21

Step 2: Substitute −y + 21 for x in 25x + 14.5y = 357:

25x + 14.5y = 357

25(−y + 21) + 14.5y = 357

−10.5y + 525 = 357 (Simplify both sides of the equation)

(−10.5y + 525) − 525 = (357) − 525(Subtract 525 to both sides)

−10.5y = −168

−10.5y / −10.5 = −168 / −10.5 (Divide both sides by -10.5)

y = 16

Step 3: Substitute 16 for y in x = −y + 21:

x = −y + 21

x = −16 + 21

x = 5 (Simplify both sides of the equation)

Answer:

x=5 and y=16