When asked to find the value of x for which f(x)=17, Danny answered 39. What
mistake did Danny make? What is the
correct answer?

Answer and Step-by-step explanation:

We are not given the function in question, but in order to explain, will form a function. Suppose f(x) = 3x + 2.

If f(x) = 17, then

3x + 2 = 17, to find the value of x, we have solve for x in the equation.

3x = 17 – 2

3x = 15

x = 5

This is the method that can be used to solve problems of this nature.

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116