The diameter for a u. s penny is 3/4 inches. how many pennies would it take to make a row 42 inches long

Let's consider the number of pennies that we need to be . Given this we can say that we are trying to find in the expression:

Let's multiply both sides by to get:

We would need 56 pennies.

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c