Eli sells t-shirts for $12 and shorts for $8. One month she sold 77 total items for $780 in total. How.many t-shirts did she sell?

Question

Can u plz solve it j don't understand

Answer 1

Variables
t = t shirts
$12 for t shirts
s = shorts
$8 for shorts

Equation 1
$12t + $8s = $780

Equation 2
t + s = 77

Use substitution method:

t = 77 - s

12 (77 - s) + 8s = 780

924 - 12 s + 8s = 780

924 - 4s = 780

-924         -924

- 4s = - 144

divide both sides by negative 1 (-1) to get rid of the negative variable

s = 36 shorts

t = 77 - 36

t = 41 t shirts

Check your answers:

$12 (41) + $8 (36) = $492 + $288 = $780