Choose all of the expressions that are equal to −9. |−9| −(−9) −|−9| −|9| the distance from zero to nine the opposite of nine

Step-by-step explanation:

Before we choose all the expression that is equal to -9, we must understand that the modulus of a value can return both its positive and negative value. For example, Modulus of b can either be +b or -b i.e |b| = +b or -b

Hence the following expression are all equal ro -9

a)  |−9| is equivalent to -9 because the absolute value of -9 i.e |−9| can return both -9 and 9

b)  −|−9| is also equivalent to -9. The modulus of -9 is also equal to 9, hence negating 9 will give us -9. This shows that  −|−9| = −|9| = −9

c)  −|9| is also equivalent to -9. This has been established in b above.

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9

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