Function Substitution and Equation Solving

This video tutorial guides viewers through solving a practice SAT math question involving functions. The problem requires determining the values of a function for given expressions and solving the resulting equation for the variable 'a'. The tutorial explains each step, from substituting values into the function to simplifying and solving the equation, ultimately finding the solution and concluding with the correct answer choice.

What is the function f(x) defined as in the problem?

• f(x) = x - 9

• f(x) = x + 9

• f(x) = x / 9

• f(x) = 9x

Tags

CCSS.HSF.IF.A.2

What is the expression for f(5a) when substituting into the function?

• 5a * 9

• 9a + 5

• 5a - 9

• 5a + 9

Tags

CCSS.HSF.IF.A.2

What is the expression for f(3a) when substituting into the function?

• 3a - 9

• 3a * 9

• 9a + 3

• 3a + 9

Tags

CCSS.HSA.REI.A.1

After substitution, what is the equation formed on the left side?

• 5a + 3

• 5a + 12

• 5a + 20

• 5a + 9

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

After substitution, what is the equation formed on the right side?

• 3a + 20

• 3a + 11

• 3a + 9

• 3a + 12

Tags

CCSS.7.EE.B.4A

What is the result after subtracting 3a from both sides of the equation?

• 2a + 9 = 8

• 2a + 12 = 20

• 2a + 9 = 20

• 2a + 12 = 8

Tags

CCSS.7.EE.B.4A

What is the value of 'a' after solving the equation?

• 2

• 6

• 8

• 4

Tags

CCSS.8.EE.C.7B

Which option corresponds to the correct answer for 'a' in the choices given?

• Option B

• Option A

• Option E

• Option C

Tags

CCSS.8.EE.C.7B