Ava bought some pens for $ 2 each and some pencils for $ 1 each. She bought 3 more pens than pencils and spent a total of $ 12. How many pencils did Ava buy?

Step-by-step explanation:

price of 1 pen= $ 2

price of 1 pencil= $1

total money spent= $12

Let the number of pen be a and number of pencil be b.

 2 a + b = 12   Equation 1

We have, she bought 3 more pens than pencils

  a - b = 3    Equation 2

 Equation 1 +Equation 2,  

   2 a + b +  a - b = 12 + 3

                     3a = 15

                     a = 5

 Substituting in  equation

           5 - b = 3

               b = 2

 Number pencils Ava bought = 2

9

step-by-step explanation:

y = 5x + 17

step-by-step explanation:

a perpendicular line will be the opposite reciprocal slope of the given equation.   the slope given is -1/5 so the opposite reciprocal is 5

find b:

7 = 5 (-2) + b

7 = -10 + b

17 = b

write equation

y = 5x + 17