5. on one day, four cooks and four waiters earned $360. on another day, working the same number of
hours and at the same rate of pay, five cooks and six waiters earned $480. how much does a cook and
how much does a waiter earn each day?

Step-by-step explanation:

c = cooks, w = waiter

4c + 4w = 360multiply by -5

5c + 6w = 480...multiply by 4

-20c - 20w = - 1800 (result of multiplying by -5)

20c + 24w = 1920 (result of multiplying by 4)

4w = 120

w = 120 / 4

w = 30 <=== waiters make $ 30

4c + 4w = 360

4c + 4(30) = 360

4c + 120 = 360

4c = 360 -120

4c = 240

c = 240/4

c = 60 <=== cooks make $ 60

it is contrapositive

i could not see the question too well so check yourself again too . this is because i want you to get it correct.

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!