Akarate studio charges $35 for the first course and $22.50 for each course after that, even if the student leaves the course early.
cena paid $170 for her son to take courses. how many courses did he take?
6 courses
7 courses
8 courses
10 courses

 The correct option is (B) 7.

Step-by-step explanation:  Given that a karate studio charges $35 for the first course and $22.50 for each course after that, even if the student leaves the course early.

Cena paid $170 for her son to take courses.

We are to find the number of courses that he took.

Let x represents the number of courses that Cena took.

Then, according to the given information, we have

Thus, the required number of courses that Cena took is 7.

Option (B) is CORRECT.

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

$75.00

step-by-step explanation:

i = prt

i = 1,5000 * 0.025 * 2

i = 75