On the function machine shown below, the function rule is given as a variable expression. When the output is 99, what is the input? * a 20

b 9

c 100

d 10

option d.

Step-by-step explanation:

We have the function:

y = f(x) = x^2  - 1

The output is 99 when y = 99, and the input is x.

Then we need to solve:

y = 99 = x^2 - 1

for x.

99 = x^2 - 1

99 + 1  =x^2

100 = x^2

√100 = x

10 = x

The correct option is d, input equals 10.

correct answer is infinitely many solutions

step-by-step explanation:

2(2x + 3) = -4 + 2(2x + 5)

solving the above equation:

4x + 6 = -4 +4x +10

combining like terms

4x -4x = -4+10-6

0=0

since both sides are 0=0, we end up into true statement it means it has infinite many solutions.

so correct answer is infinitely many solutions